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  • How we can lock a table using PHP / Drupal

    - by Kamal Challa
    Hi iam developing a module in Drupal, which needs to have a locking machanism, When one user operating on form submission other should nt take action, How do i can achieve this in php/drupal iam using mysql database with MyISAM/INNODB Please help me Thanks in advance Kamal

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  • Two strange efficiency problems in Mathematica

    - by Jess Riedel
    FIRST PROBLEM I have timed how long it takes to compute the following statements (where V[x] is a time-intensive function call): Alice = Table[V[i],{i,1,300},{1000}]; Bob = Table[Table[V[i],{i,1,300}],{1000}]^tr; Chris_pre = Table[V[i],{i,1,300}]; Chris = Table[Chris_pre,{1000}]^tr; Alice, Bob, and Chris are identical matricies computed 3 slightly different ways. I find that Chris is computed 1000 times faster than Alice and Bob. It is not surprising that Alice is computed 1000 times slower because, naively, the function V must be called 1000 more times than when Chris is computed. But it is very surprising that Bob is so slow, since he is computed identically to Chris except that Chris stores the intermediate step Chris_pre. Why does Bob evaluate so slowly? SECOND PROBLEM Suppose I want to compile a function in Mathematica of the form f(x)=x+y where "y" is a constant fixed at compile time (but which I prefer not to directly replace in the code with its numerical because I want to be able to easily change it). If y's actual value is y=7.3, and I define f1=Compile[{x},x+y] f2=Compile[{x},x+7.3] then f1 runs 50% slower than f2. How do I make Mathematica replace "y" with "7.3" when f1 is compiled, so that f1 runs as fast as f2? Many thanks!

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  • Windows forms application blocks after station lock

    - by Silviu
    We're having a serious issue at work. We've discovered that after the station where the client was running is locked/unlocked the client is blocked. No repaint. So the UI thread is blocked with something. Looking at the callstack of the UI thread (thread 0) using windbg we see that a UserPreferenceChanged event gets raised. It is marshalled through a WindowsFormsSynchronizationContext using it's controlToSend field to the UI. It gets blocked by a call to the marshalling control. The method called is MarshaledInvoke it builds a ThreadMethodEntry entry = new ThreadMethodEntry(caller, method, args, synchronous, executionContext); This entry is supposed to do the magic. The call is a synchronous call and because of that (still in the MarshaledInvoke of the Control class) the wait call is reached: if (!entry.IsCompleted) { this.WaitForWaitHandle(entry.AsyncWaitHandle); } The last thing that i can see on the stack is the WaitOne called on the previously mentioned AsyncWaitHandle. This is very annoying because having just the callstack of the runtime and not one of our methods being invoked we cannot really point to a bug in our code. I might be wrong, but I'm guessing that the marshaling control is not "marshaling" to the ui thread. But another one...i don't really know which one because the other threads are being used by us and are blocked...maybe this is the issue. But none of the other threads are running a message loop. This is very annoying. We had some issues in the past with marshaling controls to the right ui thread. That is because the first form that is constructed is a splash form. Which is not the main form. We used to use the main form to marshal call to the ui thread. But from time to time some calls would go to a non ui thread and some grids would broke with a big red X on them. I fixed this by creating a specific class: public class WindowsFormsSynchronizer { private static readonly WindowsFormsSynchronizationContext = new WindowsFormsSynchronizationContext(); //Methods are following that would build the same interface of the synchronization context. } This class gets build as one of the first objects in the first form being constructed. We've noticed some other strange thing. Looking at the heap there are 7 WindowsFormsSynchronizationContext objects. 6 of these have the same instance of controlToSend, and the other one has some different instance of controlToSend. This last one is the one that should marshal the calls to the UI. I don't have any other idea...maybe some of you guys had this same issue?

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  • PTLQueue : a scalable bounded-capacity MPMC queue

    - by Dave
    Title: Fast concurrent MPMC queue -- I've used the following concurrent queue algorithm enough that it warrants a blog entry. I'll sketch out the design of a fast and scalable multiple-producer multiple-consumer (MPSC) concurrent queue called PTLQueue. The queue has bounded capacity and is implemented via a circular array. Bounded capacity can be a useful property if there's a mismatch between producer rates and consumer rates where an unbounded queue might otherwise result in excessive memory consumption by virtue of the container nodes that -- in some queue implementations -- are used to hold values. A bounded-capacity queue can provide flow control between components. Beware, however, that bounded collections can also result in resource deadlock if abused. The put() and take() operators are partial and wait for the collection to become non-full or non-empty, respectively. Put() and take() do not allocate memory, and are not vulnerable to the ABA pathologies. The PTLQueue algorithm can be implemented equally well in C/C++ and Java. Partial operators are often more convenient than total methods. In many use cases if the preconditions aren't met, there's nothing else useful the thread can do, so it may as well wait via a partial method. An exception is in the case of work-stealing queues where a thief might scan a set of queues from which it could potentially steal. Total methods return ASAP with a success-failure indication. (It's tempting to describe a queue or API as blocking or non-blocking instead of partial or total, but non-blocking is already an overloaded concurrency term. Perhaps waiting/non-waiting or patient/impatient might be better terms). It's also trivial to construct partial operators by busy-waiting via total operators, but such constructs may be less efficient than an operator explicitly and intentionally designed to wait. A PTLQueue instance contains an array of slots, where each slot has volatile Turn and MailBox fields. The array has power-of-two length allowing mod/div operations to be replaced by masking. We assume sensible padding and alignment to reduce the impact of false sharing. (On x86 I recommend 128-byte alignment and padding because of the adjacent-sector prefetch facility). Each queue also has PutCursor and TakeCursor cursor variables, each of which should be sequestered as the sole occupant of a cache line or sector. You can opt to use 64-bit integers if concerned about wrap-around aliasing in the cursor variables. Put(null) is considered illegal, but the caller or implementation can easily check for and convert null to a distinguished non-null proxy value if null happens to be a value you'd like to pass. Take() will accordingly convert the proxy value back to null. An advantage of PTLQueue is that you can use atomic fetch-and-increment for the partial methods. We initialize each slot at index I with (Turn=I, MailBox=null). Both cursors are initially 0. All shared variables are considered "volatile" and atomics such as CAS and AtomicFetchAndIncrement are presumed to have bidirectional fence semantics. Finally T is the templated type. I've sketched out a total tryTake() method below that allows the caller to poll the queue. tryPut() has an analogous construction. Zebra stripping : alternating row colors for nice-looking code listings. See also google code "prettify" : https://code.google.com/p/google-code-prettify/ Prettify is a javascript module that yields the HTML/CSS/JS equivalent of pretty-print. -- pre:nth-child(odd) { background-color:#ff0000; } pre:nth-child(even) { background-color:#0000ff; } border-left: 11px solid #ccc; margin: 1.7em 0 1.7em 0.3em; background-color:#BFB; font-size:12px; line-height:65%; " // PTLQueue : Put(v) : // producer : partial method - waits as necessary assert v != null assert Mask = 1 && (Mask & (Mask+1)) == 0 // Document invariants // doorway step // Obtain a sequence number -- ticket // As a practical concern the ticket value is temporally unique // The ticket also identifies and selects a slot auto tkt = AtomicFetchIncrement (&PutCursor, 1) slot * s = &Slots[tkt & Mask] // waiting phase : // wait for slot's generation to match the tkt value assigned to this put() invocation. // The "generation" is implicitly encoded as the upper bits in the cursor // above those used to specify the index : tkt div (Mask+1) // The generation serves as an epoch number to identify a cohort of threads // accessing disjoint slots while s-Turn != tkt : Pause assert s-MailBox == null s-MailBox = v // deposit and pass message Take() : // consumer : partial method - waits as necessary auto tkt = AtomicFetchIncrement (&TakeCursor,1) slot * s = &Slots[tkt & Mask] // 2-stage waiting : // First wait for turn for our generation // Acquire exclusive "take" access to slot's MailBox field // Then wait for the slot to become occupied while s-Turn != tkt : Pause // Concurrency in this section of code is now reduced to just 1 producer thread // vs 1 consumer thread. // For a given queue and slot, there will be most one Take() operation running // in this section. // Consumer waits for producer to arrive and make slot non-empty // Extract message; clear mailbox; advance Turn indicator // We have an obvious happens-before relation : // Put(m) happens-before corresponding Take() that returns that same "m" for T v = s-MailBox if v != null : s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 // unlock slot to admit next producer and consumer return v Pause tryTake() : // total method - returns ASAP with failure indication for auto tkt = TakeCursor slot * s = &Slots[tkt & Mask] if s-Turn != tkt : return null T v = s-MailBox // presumptive return value if v == null : return null // ratify tkt and v values and commit by advancing cursor if CAS (&TakeCursor, tkt, tkt+1) != tkt : continue s-MailBox = null ST-ST barrier s-Turn = tkt + Mask + 1 return v The basic idea derives from the Partitioned Ticket Lock "PTL" (US20120240126-A1) and the MultiLane Concurrent Bag (US8689237). The latter is essentially a circular ring-buffer where the elements themselves are queues or concurrent collections. You can think of the PTLQueue as a partitioned ticket lock "PTL" augmented to pass values from lock to unlock via the slots. Alternatively, you could conceptualize of PTLQueue as a degenerate MultiLane bag where each slot or "lane" consists of a simple single-word MailBox instead of a general queue. Each lane in PTLQueue also has a private Turn field which acts like the Turn (Grant) variables found in PTL. Turn enforces strict FIFO ordering and restricts concurrency on the slot mailbox field to at most one simultaneous put() and take() operation. PTL uses a single "ticket" variable and per-slot Turn (grant) fields while MultiLane has distinct PutCursor and TakeCursor cursors and abstract per-slot sub-queues. Both PTL and MultiLane advance their cursor and ticket variables with atomic fetch-and-increment. PTLQueue borrows from both PTL and MultiLane and has distinct put and take cursors and per-slot Turn fields. Instead of a per-slot queues, PTLQueue uses a simple single-word MailBox field. PutCursor and TakeCursor act like a pair of ticket locks, conferring "put" and "take" access to a given slot. PutCursor, for instance, assigns an incoming put() request to a slot and serves as a PTL "Ticket" to acquire "put" permission to that slot's MailBox field. To better explain the operation of PTLQueue we deconstruct the operation of put() and take() as follows. Put() first increments PutCursor obtaining a new unique ticket. That ticket value also identifies a slot. Put() next waits for that slot's Turn field to match that ticket value. This is tantamount to using a PTL to acquire "put" permission on the slot's MailBox field. Finally, having obtained exclusive "put" permission on the slot, put() stores the message value into the slot's MailBox. Take() similarly advances TakeCursor, identifying a slot, and then acquires and secures "take" permission on a slot by waiting for Turn. Take() then waits for the slot's MailBox to become non-empty, extracts the message, and clears MailBox. Finally, take() advances the slot's Turn field, which releases both "put" and "take" access to the slot's MailBox. Note the asymmetry : put() acquires "put" access to the slot, but take() releases that lock. At any given time, for a given slot in a PTLQueue, at most one thread has "put" access and at most one thread has "take" access. This restricts concurrency from general MPMC to 1-vs-1. We have 2 ticket locks -- one for put() and one for take() -- each with its own "ticket" variable in the form of the corresponding cursor, but they share a single "Grant" egress variable in the form of the slot's Turn variable. Advancing the PutCursor, for instance, serves two purposes. First, we obtain a unique ticket which identifies a slot. Second, incrementing the cursor is the doorway protocol step to acquire the per-slot mutual exclusion "put" lock. The cursors and operations to increment those cursors serve double-duty : slot-selection and ticket assignment for locking the slot's MailBox field. At any given time a slot MailBox field can be in one of the following states: empty with no pending operations -- neutral state; empty with one or more waiting take() operations pending -- deficit; occupied with no pending operations; occupied with one or more waiting put() operations -- surplus; empty with a pending put() or pending put() and take() operations -- transitional; or occupied with a pending take() or pending put() and take() operations -- transitional. The partial put() and take() operators can be implemented with an atomic fetch-and-increment operation, which may confer a performance advantage over a CAS-based loop. In addition we have independent PutCursor and TakeCursor cursors. Critically, a put() operation modifies PutCursor but does not access the TakeCursor and a take() operation modifies the TakeCursor cursor but does not access the PutCursor. This acts to reduce coherence traffic relative to some other queue designs. It's worth noting that slow threads or obstruction in one slot (or "lane") does not impede or obstruct operations in other slots -- this gives us some degree of obstruction isolation. PTLQueue is not lock-free, however. The implementation above is expressed with polite busy-waiting (Pause) but it's trivial to implement per-slot parking and unparking to deschedule waiting threads. It's also easy to convert the queue to a more general deque by replacing the PutCursor and TakeCursor cursors with Left/Front and Right/Back cursors that can move either direction. Specifically, to push and pop from the "left" side of the deque we would decrement and increment the Left cursor, respectively, and to push and pop from the "right" side of the deque we would increment and decrement the Right cursor, respectively. We used a variation of PTLQueue for message passing in our recent OPODIS 2013 paper. ul { list-style:none; padding-left:0; padding:0; margin:0; margin-left:0; } ul#myTagID { padding: 0px; margin: 0px; list-style:none; margin-left:0;} -- -- There's quite a bit of related literature in this area. I'll call out a few relevant references: Wilson's NYU Courant Institute UltraComputer dissertation from 1988 is classic and the canonical starting point : Operating System Data Structures for Shared-Memory MIMD Machines with Fetch-and-Add. Regarding provenance and priority, I think PTLQueue or queues effectively equivalent to PTLQueue have been independently rediscovered a number of times. See CB-Queue and BNPBV, below, for instance. But Wilson's dissertation anticipates the basic idea and seems to predate all the others. Gottlieb et al : Basic Techniques for the Efficient Coordination of Very Large Numbers of Cooperating Sequential Processors Orozco et al : CB-Queue in Toward high-throughput algorithms on many-core architectures which appeared in TACO 2012. Meneghin et al : BNPVB family in Performance evaluation of inter-thread communication mechanisms on multicore/multithreaded architecture Dmitry Vyukov : bounded MPMC queue (highly recommended) Alex Otenko : US8607249 (highly related). John Mellor-Crummey : Concurrent queues: Practical fetch-and-phi algorithms. Technical Report 229, Department of Computer Science, University of Rochester Thomasson : FIFO Distributed Bakery Algorithm (very similar to PTLQueue). Scott and Scherer : Dual Data Structures I'll propose an optimization left as an exercise for the reader. Say we wanted to reduce memory usage by eliminating inter-slot padding. Such padding is usually "dark" memory and otherwise unused and wasted. But eliminating the padding leaves us at risk of increased false sharing. Furthermore lets say it was usually the case that the PutCursor and TakeCursor were numerically close to each other. (That's true in some use cases). We might still reduce false sharing by incrementing the cursors by some value other than 1 that is not trivially small and is coprime with the number of slots. Alternatively, we might increment the cursor by one and mask as usual, resulting in a logical index. We then use that logical index value to index into a permutation table, yielding an effective index for use in the slot array. The permutation table would be constructed so that nearby logical indices would map to more distant effective indices. (Open question: what should that permutation look like? Possibly some perversion of a Gray code or De Bruijn sequence might be suitable). As an aside, say we need to busy-wait for some condition as follows : "while C == 0 : Pause". Lets say that C is usually non-zero, so we typically don't wait. But when C happens to be 0 we'll have to spin for some period, possibly brief. We can arrange for the code to be more machine-friendly with respect to the branch predictors by transforming the loop into : "if C == 0 : for { Pause; if C != 0 : break; }". Critically, we want to restructure the loop so there's one branch that controls entry and another that controls loop exit. A concern is that your compiler or JIT might be clever enough to transform this back to "while C == 0 : Pause". You can sometimes avoid this by inserting a call to a some type of very cheap "opaque" method that the compiler can't elide or reorder. On Solaris, for instance, you could use :"if C == 0 : { gethrtime(); for { Pause; if C != 0 : break; }}". It's worth noting the obvious duality between locks and queues. If you have strict FIFO lock implementation with local spinning and succession by direct handoff such as MCS or CLH,then you can usually transform that lock into a queue. Hidden commentary and annotations - invisible : * And of course there's a well-known duality between queues and locks, but I'll leave that topic for another blog post. * Compare and contrast : PTLQ vs PTL and MultiLane * Equivalent : Turn; seq; sequence; pos; position; ticket * Put = Lock; Deposit Take = identify and reserve slot; wait; extract & clear; unlock * conceptualize : Distinct PutLock and TakeLock implemented as ticket lock or PTL Distinct arrival cursors but share per-slot "Turn" variable provides exclusive role-based access to slot's mailbox field put() acquires exclusive access to a slot for purposes of "deposit" assigns slot round-robin and then acquires deposit access rights/perms to that slot take() acquires exclusive access to slot for purposes of "withdrawal" assigns slot round-robin and then acquires withdrawal access rights/perms to that slot At any given time, only one thread can have withdrawal access to a slot at any given time, only one thread can have deposit access to a slot Permissible for T1 to have deposit access and T2 to simultaneously have withdrawal access * round-robin for the purposes of; role-based; access mode; access role mailslot; mailbox; allocate/assign/identify slot rights; permission; license; access permission; * PTL/Ticket hybrid Asymmetric usage ; owner oblivious lock-unlock pairing K-exclusion add Grant cursor pass message m from lock to unlock via Slots[] array Cursor performs 2 functions : + PTL ticket + Assigns request to slot in round-robin fashion Deconstruct protocol : explication put() : allocate slot in round-robin fashion acquire PTL for "put" access store message into slot associated with PTL index take() : Acquire PTL for "take" access // doorway step seq = fetchAdd (&Grant, 1) s = &Slots[seq & Mask] // waiting phase while s-Turn != seq : pause Extract : wait for s-mailbox to be full v = s-mailbox s-mailbox = null Release PTL for both "put" and "take" access s-Turn = seq + Mask + 1 * Slot round-robin assignment and lock "doorway" protocol leverage the same cursor and FetchAdd operation on that cursor FetchAdd (&Cursor,1) + round-robin slot assignment and dispersal + PTL/ticket lock "doorway" step waiting phase is via "Turn" field in slot * PTLQueue uses 2 cursors -- put and take. Acquire "put" access to slot via PTL-like lock Acquire "take" access to slot via PTL-like lock 2 locks : put and take -- at most one thread can access slot's mailbox Both locks use same "turn" field Like multilane : 2 cursors : put and take slot is simple 1-capacity mailbox instead of queue Borrow per-slot turn/grant from PTL Provides strict FIFO Lock slot : put-vs-put take-vs-take at most one put accesses slot at any one time at most one put accesses take at any one time reduction to 1-vs-1 instead of N-vs-M concurrency Per slot locks for put/take Release put/take by advancing turn * is instrumental in ... * P-V Semaphore vs lock vs K-exclusion * See also : FastQueues-excerpt.java dice-etc/queue-mpmc-bounded-blocking-circular-xadd/ * PTLQueue is the same as PTLQB - identical * Expedient return; ASAP; prompt; immediately * Lamport's Bakery algorithm : doorway step then waiting phase Threads arriving at doorway obtain a unique ticket number Threads enter in ticket order * In the terminology of Reed and Kanodia a ticket lock corresponds to the busy-wait implementation of a semaphore using an eventcount and a sequencer It can also be thought of as an optimization of Lamport's bakery lock was designed for fault-tolerance rather than performance Instead of spinning on the release counter, processors using a bakery lock repeatedly examine the tickets of their peers --

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  • Store a formula in a table and use the formula in a javascript/PHP function

    - by Muhaimin Abdul
    I have a MySql database where part of it handles instrument's depth of water. Each instrument has its own formula of calculation how depth the water when the operator collect the reading I stored the formula for each instrument in database/MySql. Example formula: [55-57] this is the simple minus operation, where the number is actually represent the id of a row. How do I represent those number with id of a row and later convert it to javascript readable code. I simply want to do keyup event where everytime user key in something into text field then the other part of HTML would reflect changes based on formula that I fetched from database FYI, I'm using BackboneJS together with RequireJS

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  • How do I align my partition table properly?

    - by Jorge Castro
    I am in the process of building my first RAID5 array. I've used mdadm to create the following set up: root@bondigas:~# mdadm --detail /dev/md1 /dev/md1: Version : 00.90 Creation Time : Wed Oct 20 20:00:41 2010 Raid Level : raid5 Array Size : 5860543488 (5589.05 GiB 6001.20 GB) Used Dev Size : 1953514496 (1863.02 GiB 2000.40 GB) Raid Devices : 4 Total Devices : 4 Preferred Minor : 1 Persistence : Superblock is persistent Update Time : Wed Oct 20 20:13:48 2010 State : clean, degraded, recovering Active Devices : 3 Working Devices : 4 Failed Devices : 0 Spare Devices : 1 Layout : left-symmetric Chunk Size : 64K Rebuild Status : 1% complete UUID : f6dc829e:aa29b476:edd1ef19:85032322 (local to host bondigas) Events : 0.12 Number Major Minor RaidDevice State 0 8 16 0 active sync /dev/sdb 1 8 32 1 active sync /dev/sdc 2 8 48 2 active sync /dev/sdd 4 8 64 3 spare rebuilding /dev/sde While that's going I decided to format the beast with the following command: root@bondigas:~# mkfs.ext4 /dev/md1p1 mke2fs 1.41.11 (14-Mar-2010) /dev/md1p1 alignment is offset by 63488 bytes. This may result in very poor performance, (re)-partitioning suggested. Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=16 blocks, Stripe width=48 blocks 97853440 inodes, 391394047 blocks 19569702 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=0 11945 block groups 32768 blocks per group, 32768 fragments per group 8192 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968, 102400000, 214990848 Writing inode tables: ^C 27/11945 root@bondigas:~# ^C I am unsure what to do about "/dev/md1p1 alignment is offset by 63488 bytes." and how to properly partition the disks to match so I can format it properly.

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  • SQL Bits X – Temporal Snapshot Fact Table Session Slide & Demos

    - by Davide Mauri
    Already 10 days has passed since SQL Bits X in London. I really enjoyed it! Those kind of events are great not only for the content but also to meet friends that – due to distance – is not possible to meet every day. Friends from PASS, SQL CAT, Microsoft, MVP and so on all in one place, drinking beers, whisky and having fun. A perfect mixture for a great learning and sharing experience! I’ve also enjoyed a lot delivering my session on Temporal Snapshot Fact Tables. Given that the subject is very specific I was not expecting a lot of attendees….but I was totally wrong! It seems that the problem of handling daily snapshot of data is more common than what I expected. I’ve also already had feedback from several attendees that applied the explained technique to their existing solution with success. This is just what a speaker in such conference wish to hear! :) If you want to take a look at the slides and the demos, you can find them on SkyDrive: https://skydrive.live.com/redir.aspx?cid=377ea1391487af21&resid=377EA1391487AF21!1151&parid=root The demo is available both for SQL Sever 2008 and for SQL Server 2012. With this last version, you can also simplify the ETL process using the new LEAD analytic function. (This is not done in the demo, I’ve left this option as a little exercise for you :) )

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  • MYSQL Merging 2 results into 1 table

    - by AlphaRomeo69
    Im building a c# program and am currently stuck at fetching data from MYSQL database and bind them to a grid view. I had been researching for a few days now but to no avail. I have 4 table in the database. table 1 - alpha table 2 - bravo table 3 - charlie table 4 - delta attributes of alpha (id, type, user, role ) attributes of bravo (id, type, date, user) attributes of charlie (id,type, cat, doneby, comment) atttibutes of delta (id,type, cat, doneby) * the pk of alpha and bravo is (id) * the pk of charlie and delta is (id, type) i did a query1 before by inner joinning alpha, bravo and charlie which leads to the sucessful result of (id, type, date, user, role, cat, doneby, comment) and i also did a query2 before by inner joinning alpha, bravo and delta which leads to the sucessful result of (id, type, date, user, role, cat, doneby) Right now, im trying to built a query3 which will merge the result from query1 and query2 together. the result of my attempts leads to (id, type, date, user, role, cat, doneby, comment,id, type, date, user, role, cat, doneby) As i do not want the repeated columns, I would like to seek advice on how to get the result to become like the one below by placing the records as a new tuple in the result table. (id, type, date, user, role, cat, doneby, comment) Thanks! P.S: the PK would not pose a problem due to (id, type)

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  • UIKeyboard turn Caps Lock on

    - by Daniel Granger
    I need my user to input some data like DF-DJSL so I put this in the code: theTextField.autocapitalizationType = UITextAutocapitalizationTypeAllCharacters; But unfortunately what happens is the first to letter type in CAPS but then letter immediately after typing the hyphen will be in lower case and then the rest return to CAPS therefore producing output like this (unless the user manually taps the shift button after typing a hyphen): DF-dJSL How can I fix this? Many Thanks

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  • ActiveRecord table inheritence using set_table_names

    - by Jinyoung Kim
    Hi, I'm using ActiveRecord in Ruby on Rails. I have a table named documents(Document class) and I want to have another table data_documents(DataDocument) class which is effectively the same except for having different table name. In other words, I want two tables with the same behavior except for table name. class DataDocument < Document #set_table_name "data_documents" self.table_name = "data_documents" end My solution was to use class inheritance as above, yet this resulted in inconsistent SQL statement for create operation where there are both 'documents' table and 'data_documents' table. Can you figure out why and how I can make it work? >> DataDocument.create(:did=>"dd") ActiveRecord::StatementInvalid: Mysql::Error: Unknown column 'data_documents.did' in 'where clause': SELECT `documents`.id FROM `documents` WHERE (`data_documents`.`did` = BINARY 'dd') LIMIT 1 from /Users/lifidea/.gem/ruby/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract_adapter.rb:212:in `log' from /Users/lifidea/.gem/ruby/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/mysql_adapter.rb:320:in `execute' from /Users/lifidea/.gem/ruby/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/mysql_adapter.rb:595:in `select' from /Users/lifidea/.gem/ruby/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/database_statements.rb:7:in `select_all_without_query_cache' from /Users/lifidea/.gem/ruby/1.8/gems/activerecord-2.3.2/lib/active_record/connection_adapters/abstract/query_cache.rb:62:in `select_all'

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  • Evaluation of CTEs in SQL Server 2005

    - by Jammer
    I have a question about how MS SQL evaluates functions inside CTEs. A couple of searches didn't turn up any results related to this issue, but I apologize if this is common knowledge and I'm just behind the curve. It wouldn't be the first time :-) This query is a simplified (and obviously less dynamic) version of what I'm actually doing, but it does exhibit the problem I'm experiencing. It looks like this: CREATE TABLE #EmployeePool(EmployeeID int, EmployeeRank int); INSERT INTO #EmployeePool(EmployeeID, EmployeeRank) SELECT 42, 1 UNION ALL SELECT 43, 2; DECLARE @NumEmployees int; SELECT @NumEmployees = COUNT(*) FROM #EmployeePool; WITH RandomizedCustomers AS ( SELECT CAST(c.Criteria AS int) AS CustomerID, dbo.fnUtil_Random(@NumEmployees) AS RandomRank FROM dbo.fnUtil_ParseCriteria(@CustomerIDs, 'int') c) SELECT rc.CustomerID, ep.EmployeeID FROM RandomizedCustomers rc JOIN #EmployeePool ep ON ep.EmployeeRank = rc.RandomRank; DROP TABLE #EmployeePool; The following can be assumed about all executions of the above: The result of dbo.fnUtil_Random() is always an int value greater than zero and less than or equal to the argument passed in. Since it's being called above with @NumEmployees which has the value 2, this function always evaluates to 1 or 2. The result of dbo.fnUtil_ParseCriteria(@CustomerIDs, 'int') produces a one-column, one-row table that contains a sql_variant with a base type of 'int' that has the value 219935. Given the above assumptions, it makes sense (to me, anyway) that the result of the expression above should always produce a two-column table containing one record - CustomerID and an EmployeeID. The CustomerID should always be the int value 219935, and the EmployeeID should be either 42 or 43. However, this is not always the case. Sometimes I get the expected single record. Other times I get two records (one for each EmployeeID), and still others I get no records. However, if I replace the RandomizedCustomers CTE with a true temp table, the problem vanishes completely. Every time I think I have an explanation for this behavior, it turns out to not make sense or be impossible, so I literally cannot explain why this would happen. Since the problem does not happen when I replace the CTE with a temp table, I can only assume it has something to do with the functions inside CTEs are evaluated during joins to that CTE. Do any of you have any theories?

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  • Using a PivotTable to Count Items in Access

    - by Sandra
    I have a list of text entries and I want to count how often each entry appears in the list. e.g. Berlin Paris London London Paris Paris Paris The result would be Berlin 1 Paris 4 London 2 This result easy do to achieve with an pivot table in MS Excel (see: Count Items in Excel). My data not in spreadsheet in Excel but in a MS Access database table. So in order to avoid constant switching between Access and Excel and I would like to handle everything in Access (either Access 2007 or 2010). I know there are pivot tables in Access and I know how to display one, but I was unable to find out how to count the number of occurrences. Thank you!

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  • Does query plan optimizer works well with joined/filtered table-valued functions?

    - by smoothdeveloper
    In SQLSERVER 2005, I'm using table-valued function as a convenient way to perform arbitrary aggregation on subset data from large table (passing date range or such parameters). I'm using theses inside larger queries as joined computations and I'm wondering if the query plan optimizer work well with them in every condition or if I'm better to unnest such computation in my larger queries. Does query plan optimizer unnest table-valued functions if it make sense? If it doesn't, what do you recommend to avoid code duplication that would occur by manually unnesting them? If it does, how do you identify that from the execution plan? code sample: create table dbo.customers ( [key] uniqueidentifier , constraint pk_dbo_customers primary key ([key]) ) go /* assume large amount of data */ create table dbo.point_of_sales ( [key] uniqueidentifier , customer_key uniqueidentifier , constraint pk_dbo_point_of_sales primary key ([key]) ) go create table dbo.product_ranges ( [key] uniqueidentifier , constraint pk_dbo_product_ranges primary key ([key]) ) go create table dbo.products ( [key] uniqueidentifier , product_range_key uniqueidentifier , release_date datetime , constraint pk_dbo_products primary key ([key]) , constraint fk_dbo_products_product_range_key foreign key (product_range_key) references dbo.product_ranges ([key]) ) go . /* assume large amount of data */ create table dbo.sales_history ( [key] uniqueidentifier , product_key uniqueidentifier , point_of_sale_key uniqueidentifier , accounting_date datetime , amount money , quantity int , constraint pk_dbo_sales_history primary key ([key]) , constraint fk_dbo_sales_history_product_key foreign key (product_key) references dbo.products ([key]) , constraint fk_dbo_sales_history_point_of_sale_key foreign key (point_of_sale_key) references dbo.point_of_sales ([key]) ) go create function dbo.f_sales_history_..snip.._date_range ( @accountingdatelowerbound datetime, @accountingdateupperbound datetime ) returns table as return ( select pos.customer_key , sh.product_key , sum(sh.amount) amount , sum(sh.quantity) quantity from dbo.point_of_sales pos inner join dbo.sales_history sh on sh.point_of_sale_key = pos.[key] where sh.accounting_date between @accountingdatelowerbound and @accountingdateupperbound group by pos.customer_key , sh.product_key ) go -- TODO: insert some data -- this is a table containing a selection of product ranges declare @selectedproductranges table([key] uniqueidentifier) -- this is a table containing a selection of customers declare @selectedcustomers table([key] uniqueidentifier) declare @low datetime , @up datetime -- TODO: set top query parameters . select saleshistory.customer_key , saleshistory.product_key , saleshistory.amount , saleshistory.quantity from dbo.products p inner join @selectedproductranges productrangeselection on p.product_range_key = productrangeselection.[key] inner join @selectedcustomers customerselection on 1 = 1 inner join dbo.f_sales_history_..snip.._date_range(@low, @up) saleshistory on saleshistory.product_key = p.[key] and saleshistory.customer_key = customerselection.[key] I hope the sample makes sense. Much thanks for your help!

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  • SQL SERVER Size of Index Table for Each Index Solution 3 Powershell

    Laerte Junior If you are a Powershell user, the name of the Laerte Junior is not a new name. He is the one man with exceptional knowledge of Powershell. He is not only very knowledgeable, but also very kind and eager to those in need. I have been attempting to setup Powershell for many days, [...]...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • SQL SERVER Size of Index Table for Each Index Solution 3 Powershell

    Laerte Junior If you are a Powershell user, the name of the Laerte Junior is not a new name. He is the one man with exceptional knowledge of Powershell. He is not only very knowledgeable, but also very kind and eager to those in need. I have been attempting to setup Powershell for many days, [...]...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • IOException: Unable To Delete Images Due To File Lock

    - by Arslan Pervaiz
    I am Unable To Delete Image File From My Server Path It Gaves Error That The Process Cannot Access The File "FileName" Because it is being Used By Another Process. I Tried Many Methods But Still All In Vain. Please Help me Out in This Issue. Here is My Code Snippet. using System; using System.Data; using System.Web; using System.Data.SqlClient; using System.Web.UI; using System.Web.UI.HtmlControls; using System.Globalization; using System.Web.Security; using System.Text; using System.DirectoryServices; using System.Collections; using System.IO; using System.Drawing; using System.Drawing.Imaging; using System.Drawing.Drawing2D; //============ Main Block ================= byte[] data = (byte[])ds.Tables[0].Rows[0][0]; MemoryStream ms = new MemoryStream(data); Image returnImage = Image.FromStream(ms); returnImage.Save(Server.MapPath(".\\TmpImages\\SavedImage.jpg"), System.Drawing.Imaging.ImageFormat.Jpeg); returnImage.Dispose(); \\ I Tried this Dispose Method To Unlock The File But Nothing Done. ms.Close(); \\ I Tried The Memory Stream Close Method Also But Its Also Not Worked For Me. watermark(); \\ Here is My Water Mark Method That Print Water Mark Image on My Saved Image (Image That is Converted From Byte Array) DeleteImages(); \\ Here is My Delete Method That I Call To Delete The Images //===== ==== My Delete Method To Delete Files================== public void DeleteImages() { try { File.Delete(Server.MapPath(".\\TmpImages\\WaterMark.jpg")); \\This Image Deleted Fine. File.Delete(Server.MapPath(".\\TmpImages\\SavedImage.jpg")); \\ Exception Thrown On Deleting of This Image. } catch (Exception ex) { LogManager.LogException(ex, "Error in Deleting Images."); Master.ShowMessage(ex.Message, true); } } \ ==== Method Declartion That Make Watermark of One Image On Another Image.======= public void watermark() { //create a image object containing the photograph to watermark Image imgPhoto = Image.FromFile(Server.MapPath(".\\TmpImages\\SavedImage.jpg")); int phWidth = imgPhoto.Width; int phHeight = imgPhoto.Height; //create a Bitmap the Size of the original photograph Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb); bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution); //load the Bitmap into a Graphics object Graphics grPhoto = Graphics.FromImage(bmPhoto); //create a image object containing the watermark Image imgWatermark = new Bitmap(Server.MapPath(".\\TmpImages\\PrintasWatermark.jpg")); int wmWidth = imgWatermark.Width; int wmHeight = imgWatermark.Height; //Set the rendering quality for this Graphics object grPhoto.SmoothingMode = SmoothingMode.AntiAlias; //Draws the photo Image object at original size to the graphics object. grPhoto.DrawImage( imgPhoto, // Photo Image object new Rectangle(0, 0, phWidth, phHeight), // Rectangle structure 0, // x-coordinate of the portion of the source image to draw. 0, // y-coordinate of the portion of the source image to draw. phWidth, // Width of the portion of the source image to draw. phHeight, // Height of the portion of the source image to draw. GraphicsUnit.Pixel); // Units of measure //------------------------------------------------------- //to maximize the size of the Copyright message we will //test multiple Font sizes to determine the largest posible //font we can use for the width of the Photograph //define an array of point sizes you would like to consider as possiblities //------------------------------------------------------- //Define the text layout by setting the text alignment to centered StringFormat StrFormat = new StringFormat(); StrFormat.Alignment = StringAlignment.Center; //define a Brush which is semi trasparent black (Alpha set to 153) SolidBrush semiTransBrush2 = new SolidBrush(Color.FromArgb(153, 0, 0, 0)); //define a Brush which is semi trasparent white (Alpha set to 153) SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(153, 255, 255, 255)); //------------------------------------------------------------ //Step #2 - Insert Watermark image //------------------------------------------------------------ //Create a Bitmap based on the previously modified photograph Bitmap Bitmap bmWatermark = new Bitmap(bmPhoto); bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution); //Load this Bitmap into a new Graphic Object Graphics grWatermark = Graphics.FromImage(bmWatermark); //To achieve a transulcent watermark we will apply (2) color //manipulations by defineing a ImageAttributes object and //seting (2) of its properties. ImageAttributes imageAttributes = new ImageAttributes(); //The first step in manipulating the watermark image is to replace //the background color with one that is trasparent (Alpha=0, R=0, G=0, B=0) //to do this we will use a Colormap and use this to define a RemapTable ColorMap colorMap = new ColorMap(); //My watermark was defined with a background of 100% Green this will //be the color we search for and replace with transparency colorMap.OldColor = Color.FromArgb(255, 0, 255, 0); colorMap.NewColor = Color.FromArgb(0, 0, 0, 0); ColorMap[] remapTable = { colorMap }; imageAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap); //The second color manipulation is used to change the opacity of the //watermark. This is done by applying a 5x5 matrix that contains the //coordinates for the RGBA space. By setting the 3rd row and 3rd column //to 0.3f we achive a level of opacity float[][] colorMatrixElements = { new float[] {1.0f, 0.0f, 0.0f, 0.0f, 0.0f}, new float[] {0.0f, 1.0f, 0.0f, 0.0f, 0.0f}, new float[] {0.0f, 0.0f, 1.0f, 0.0f, 0.0f}, new float[] {0.0f, 0.0f, 0.0f, 0.3f, 0.0f}, new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f}}; ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements); imageAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap); //For this example we will place the watermark in the upper right //hand corner of the photograph. offset down 10 pixels and to the //left 10 pixles int xPosOfWm = ((phWidth - wmWidth) - 10); int yPosOfWm = 10; grWatermark.DrawImage(imgWatermark, new Rectangle(xPosOfWm, yPosOfWm, wmWidth, wmHeight), //Set the detination Position 0, // x-coordinate of the portion of the source image to draw. 0, // y-coordinate of the portion of the source image to draw. wmWidth, // Watermark Width wmHeight, // Watermark Height GraphicsUnit.Pixel, // Unit of measurment imageAttributes); //ImageAttributes Object //Replace the original photgraphs bitmap with the new Bitmap imgPhoto = bmWatermark; grPhoto.Dispose(); grWatermark.Dispose(); //save new image to file system. imgPhoto.Save(Server.MapPath(".\\TmpImages\\WaterMark.jpg"), ImageFormat.Jpeg); imgPhoto.Dispose(); imgWatermark.Dispose(); }

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  • Set default expand/colapse state on pivot tables

    - by CLockeWork
    The Setup I have a pivot table in tabular form pulling data from an Analysis Services Cube. I want to calculate the number of days between two dates, but the setup will only allow me to pull in all date elements, not just the date. I’ve been able to deal with this easily enough by just grouping all the columns: The Problem The default state for the expand/collapse buttons in the image above is often collapsed, but that means the dates I need aren’t there and you have to open the group and manually expand them. This also happens in some random ways (as shown in the image) where only some rows expand. The Question I need a way to set these sections to always be expanded, so that the user never has to open the group to expand the rows. Ideally I’d like to avoid VBA because our end users often block it, but if that’s what’s needed then so be it. Is there a way to set my pivot table to never collapse it’s predefined groups? Note the end user is using Excel 2010

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  • Temp Table Recompiles

    - by Derek D.
    If you landed on this article, then you most likely know that temp tables can cause recompilation. This happens because temp tables are treated just like regular tables by the SQL Server Engine. When the tables (in which underlying queries rely on) change significantly, SQL Server detects this change (using auto update statistics) [...]

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  • Should all foreign table references use foreign key constraints

    - by TecBrat
    Closely related to: Foreign key restrictions -> yes or no? I asked a question on SO and it led me to ask this here. If I'm faced with a choice of having a circular reference or just not enforcing the restraint, which is the better choice? In my particular case I have customers and addresses. I want an address to have a reference to a customer and I want each customer to have a default billing address id and a default shipping address id. I might query for all addresses that have a certain customer ID or I might query for the address with the ID that matches the default shipping or billing address ids. I'm not sure yet how the constraints (or lack of) will effect the system as my application and it's data age.

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  • SQLite as an App Queue, Exclusive Row Lock?

    - by ScSub
    I am considering using SQLite as a "job queue container", and was wondering how I could do so, using custom C# (with ADO.NET) to work the database. If this was SQL Server, I would setup a serializable transaction to make sure the parent row and child rows were exclusively mine until I was done. I'm not sure how that would work in SQLite, can anyone offer any assistance? Or if there are any other existing implementations of message queueing with SQLite, I'd appreciate any pointers in that direction as well. Thanks!

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  • sql foreign keys

    - by Paul Est
    I was create tables with the syntax in phpmyadmin: DROP TABLE IF EXISTS users; DROP TABLE IF EXISTS info; CREATE TABLE users ( user_id int unsigned NOT NULL auto_increment, email varchar(100) NOT NULL default '', pwd varchar(32) NOT NULL default '', isAdmin int(1) unsigned NOT NULL, PRIMARY KEY (user_id) ) TYPE=INNODB; CREATE TABLE info ( info_id int unsigned NOT NULL auto_increment, first_name varchar(100) NOT NULL default '', last_name varchar(100) NOT NULL default '', address varchar(300) NOT NULL default '', zipcode varchar(100) NOT NULL default '', personal_phone varchar(100) NOT NULL default '', mobilephone varchar(100) NOT NULL default '', faxe varchar(100) NOT NULL default '', email2 varchar(100) NOT NULL default '', country varchar(100) NOT NULL default '', sex varchar(1) NOT NULL default '', birth varchar(1) NOT NULL default '', email varchar(100) NOT NULL default '', PRIMARY KEY (info_id), FOREIGN KEY (email) REFERENCES users(email) ON UPDATE CASCADE ON DELETE CASCADE ) TYPE=INNODB; But shows the error "#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'TYPE=INNODB' at line 11 " If i remove the TYPE=INNODB in the end of create the tables, it will show the error "#1005 - Can't create table 'curriculo.info' (errno: 150) ".

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  • VB.NET LINQ to SQL Delete All Records

    - by Daniel
    I am having problems with deleting all records in a table with VB.NET. I am using this code to delete all records in the Contacts table For Each contact In database.Contacts database.Contacts.DeleteOnSubmit(contact) Next But I get this error Can't perform Create, Update or Delete operations on 'Table(Contact)' because it has no primary key. Anyone have any suggestions? Thanks

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  • JPA optimistic lock - setting @Version to entity class cause query to include VERSION as column

    - by masato-san
    I'm using JPA Toplink Essential, Netbean6.8, GlassFish v3 In my Entity class I added @Version annotation to enable optimistic locking at transaction commit however after I added the annotation, my query started including VERSION as column thus throwing SQL exception. None of this is mentioned in any tutorial I've seen so far. What could be wrong? Snippet public class MasatosanTest2 implements Serializable { private static final long serialVersionUID = 1L; @Id @Basic(optional = false) @Column(name = "id") private Integer id; @Column(name = "username") private String username; @Column(name = "note") private String note; //here adding Version @Version int version; query used: SELECT m FROM MasatosanTest2 m Internal Exception: com.microsoft.sqlserver.jdbc.SQLServerException Call: SELECT id, username, note, VERSION FROM MasatosanTest2

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  • How to create a server control on another ASPX file

    - by salvationishere
    I am developing a C#/SQL ASP.NET web application in VS 2008. Currently, I am transferring control from one ASPX file to another: if (uploadFile.PostedFile.ContentLength > 0) { inputfile = System.IO.File.ReadAllText(path); Context.Items["Message"] = inputfile; //Page1 Server.Transfer("DataMatch.aspx"); //Page1 } However, it fails on this Server.Transfer line after inserting runat="server" in the DataMatch.aspx file to the Table element like so: <table width="50%" id="tMain" runat="server"> But after making this a server control, I rebuilt it and now when I run this app it gives me exception: Error executing child request for DataMatch.aspx But I need this table to be a server control so I can make it invisible programmatically if a certain condition occurs. How else can I programmatically make this table invisible?

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  • How to make an entity out of a join table without primary key

    - by tputkonen
    I'm trying to generate JPA entities out of an existing database having an "interesting" design. Database has a table called UserSet, which can have links to several other UserSets. There is a one to many relation between UserSets and LinkedUserSets. LinkedUserSets also has one to one relation to UserSets. I tried to generate a JPA Entity out of the database structure using Dali JPA Tools. The resulting entity Linkeduserset misses @Id or @EmbeddedId annotation and thus failes to compile. As the resulting entity contains only two @JoinColumns (which cannot be marked as @Id), I have not so far found a way around this issue. Database structure can not be modified in any way. Is there a way to overcome this somehow? Relevant pars of create table statements: CREATE TABLE `LinkedUserSets` ( `UsrSetID` INT(11) NOT NULL DEFAULT '0' , `ChildID` INT(11) NOT NULL DEFAULT '0' , CONSTRAINT `fk_LinkedUserSets_UserSet1` FOREIGN KEY (`UsrSetID` ) REFERENCES `UserSet` (`UsrSetID` )); CREATE TABLE `UserSet` ( `UsrSetID` INT(11) NOT NULL AUTO_INCREMENT , PRIMARY KEY (`UsrSetID`), CONSTRAINT `fk_UserSet_LinkedUserSets1` FOREIGN KEY (`UsrSetID` ) REFERENCES `LinkedUserSets` (`ChildID` )); Generated entities: @Entity @Table(name="linkedusersets") public class Linkeduserset { //bi-directional many-to-one association to Userset @ManyToOne @JoinColumn(name="UsrSetID") private Userset userset1; //bi-directional one-to-one association to Userset @OneToOne @JoinColumn(name="ChildID") private Userset userset2; } @Entity @Table(name="userset") public class Userset { private static final long serialVersionUID = 1L; @Id @Column(name="UsrSetID") private int jngSetID; //bi-directional many-to-one association to Linkeduserset @OneToMany(mappedBy="userset1") private Set<Linkeduserset> linkedusersets; //bi-directional one-to-one association to Linkeduserset @OneToOne(mappedBy="userset2") private Linkeduserset linkeduserset; } Error message: Entity "Linkeduserset" has no Id or EmbeddedId

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