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  • php convert european datetime to mysql datetime

    - by Mathlight
    I'm really stuck with this problem. I've got an datetime string like this: 28-06-14 11:01:00 I'm trying to convert it to 2014-06-28 11:01:00 so that i can insert it into the database ( with field type datetime. I've tryed multiple things like this: $datumHolder = new DateTime($data['datum'], new DateTimeZone('Europe/Amsterdam')); $datum1 = $datumHolder -> format("Y-m-d H:i:s"); $datum2 = date( 'Y-m-d', strtotime(str_replace('-', '/', $data['datum']) ) ); $datum3 = DateTime::createFromFormat( 'Y-m-d-:Hi:s', $data['datum']); This is the output i get: datum1: 2028-06-14 11:01:00 datum2: 1970-01-01 And i get an error for datum3: echo "datum3: " . $datum3->format( 'Y-m-d H:i:s'); . '<br />'; Call to a member function format() on a non-object So my question is very clear... What am I doing wrong / how to get this working? Thanks in advantage guys! I know that this question is asked many, many times... But whatever i try, i can't get it working...

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  • Using a comma seperated data in MYSQL "IN" clause

    - by Sashi Kant
    I have a column in one of my table where I store multiple ids seperated by comma's. Is there a way in which I can use this column's value in the "IN" clause of a query. The column(city) has values like 6,7,8,16,21,2 I need to use as Select * from table where e_ID in (Select city from locations where e_Id=?) I am satisfied with Crozin's answer, but I am open to suggestions, views and options. Feel free to share your views.

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  • Listing issue, GROUP mysql

    - by SethCodes
    Here is a mock-up example of Mysql table: | ID | Country | City | ________________________________ | 1 | Sweden | Stockholm | | 2 | Sweden | Stockholm | | 3 | Sweden | Lund | | 4 | Sweden | Lund | | 5 | Germany | Berlin | | 6 | Germany | Berlin | | 7 | Germany | Hamburg | | 8 | Germany | Hamburg | Notice how both rows Country and city have repeated values inside them. Using GROUP BY country, city in my PDO query, the values will not repeat while in loop. Here is PDO for this: $query = "SELECT id, city, country FROM table GROUP BY country, city"; $stmt = $db->query($query); while($row = $stmt->fetch(PDO::FETCH_ASSOC)) : The above code will result in an output like this (some editing in-between). GROUP BY works but the country repeats: Sweden - Stockholm Sweden - Lund Germany - Berlin Germany - Hamburg Using bootstrap collapse and above code, I separate the country from the city with a simple drop down collopase. Here is code: <li> <a data-toggle="collapse" data-target="#<?= $row['id']; ?>" href="search.php?country=<?= $row['country']; ?>"> <?= $row['country']; ?> </a> <div id ="<?= $row['id']; ?>" class="collapse in"> //collapse div here <a href="search.php?city=<?= $row['city']; ?>"> <?= $row['city']; ?><br></a> </div> //end </li> It then looks something like this (once collapse is initiated): Sweden > Stockholm Sweden > Lund Germany >Berlin Germany >Hamburg Here is where I face the problem. The above lists the values Sweden and Germany 2 times. I want Sweden and Germany to only list one time, and the cities listed below, so the desired look is to be this: Sweden // Lists one time > Stockholm > Lund Germany // Lists one time >Berlin >Hamburg I have tried using DISTINCT, GROUP_CONTACT and other methods, yet none get my desired output (above). Suggestions? Below is my current full code in action: <? $query = "SELECT id, city, country FROM table GROUP BY country, city"; $stmt = $db->query($query); while($row = $stmt->fetch(PDO::FETCH_ASSOC)) : ?> <li> <a data-toggle="collapse" data-target="#<?= $row['id']; ?>" href="search.php?country=<?= $row['country']; ?>"> <?= $row['country']; ?> </a> <div id ="<?= $row['id']; ?>" class="collapse in"> //collapse div here <a href="search.php?city=<?= $row['city']; ?>"> <?= $row['city']; ?><br></a> </div> //end </li> <? endwhile ?>

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  • Select Columns Only if String length is greater than 2

    - by Zee-pro
    Similar Question may be asked but I am unable to find anything that fits my needs. How can I select only columns where string length is greater than 2 This is how much has done yet. SELECT * FROM Table1 WHERE (Table1.ID = @ID) Or something like WHERE (Table1.ID = @ID) AND (LEN(*) > 2) Thank for all of your help I have a Table, in which I have 35 columns and a User ID column, now I want to select and display information from only those columns which have 2 string. I Like to Select only columns which have 2 string and the defined ID by User not the Whole Row !! I hope I am making sense. Table Desired Result DI 35 Lesson 4 Maths Lesson 9 ICT Lesson 12 English

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  • count(*) is it really expensive ?

    - by Anil Namde
    I have a page where i have 4 tabs displaying 4 different reports based of different tables. Now i get row count of each tabled using select count() from table query and display number of rows available in each table on the tabs. Now with each page post back 5 count() queries are executed (4 to get counts and 1 for pagination) and 1 query for getting report. Now my question is should is count(*) query really expensive that i should keep the row counts (at least which are displayed on tab) in view state of page instead of queering each time? How much expensive it is ?

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  • Why MSSQL keeps throwing me Exceptions?

    - by Augusto Càzares
    I have my project in .NET that uses a db in MSSQL Server,i'm using LINQ , sometimes when the projec throws me an exception (Constraint) in a part of the project this same error keeps showing in other part of the project when i do another thing with the db, like when i do an insertion and i had before an exception on delete the insertion throws me the delete exeption, and it remainds this way until i close and open again the project, my major problem is when this happen in my online project, this error in my project causes me problems in the project i'm testing online (i use the same db). I don't know if this exception is on the memory or something but its have been causing me a lot of headechs.

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  • When should we use Views, Temporary Tables and Direct Queries ? What are the Performance issues in a

    - by Shantanu Gupta
    I want to know the performance of using Views, Temp Tables and Direct Queries Usage in a Stored Procedure. I have a table that gets created every time when a trigger gets fired. I know this trigger will be fired very rare and only once at the time of setup. Now I have to use that created table from triggers at many places for fetching data and I confirms it that no one make any changes in that table. i.e ReadOnly Table. I have to use this tables data along with multiple tables to join and fetch result for further queries say select * from triggertable By Using temp table select ... into #tx from triggertable join t2 join t3 and so on select a,b, c from #tx --do something select d,e,f from #tx ---do somethign --and so on --around 6-7 queries in a row in a stored procedure. By Using Views create view viewname ( select ... from triggertable join t2 join t3 and so on ) select a,b, c from viewname --do something select d,e,f from viewname ---do somethign --and so on --around 6-7 queries in a row in a stored procedure. This View can be used in other places as well. So I will be creating at database rather than at sp By Using Direct Query select a,b, c from select ... into #tx from triggertable join t2 join t3 join ... --do something select a,b, c from select ... into #tx from triggertable join t2 join t3 join ... --do something . . --and so on --around 6-7 queries in a row in a stored procedure. Now I can create a view/temporary table/ directly query usage in all upcoming queries. What would be the best to use in this case.

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  • Equivalent of Switch Statement in MySql 5

    - by Robert Gowland
    Using MySql 5, I have a task where I need to update one table based on the contents of another table. For example, I need to add 'A1' to table 'A' if table 'B' contains 'B1'. I need to add 'A2a' and 'A2b' to table 'A' if table 'B' contains 'B2', etc.. In our case, the value in table 'B' we're interested is an enum. Right now I have a stored procedure containing a series of statements like: INSERT INTO A SELECT 'A1' FROM B WHERE B.Value = 'B1'; --Repeat for 'B2' -> 'A2a', 'A2b'; 'B3' -> 'A3', etc... Is there a nicer more DRY way of accomplishing this?

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  • Converting MySQL Resultset from Rows to Columns

    - by gms8994
    I have output from a select like this: 04:47:37> select * from attributes left outer join trailer_attributes on attributes.id = trailer_attributes.attribute_id; +----+--------------+----------+-----------+------------+--------------+-----------------+ | id | name | datatype | list_page | trailer_id | attribute_id | attribute_value | +----+--------------+----------+-----------+------------+--------------+-----------------+ | 1 | Make | text | 1 | 1 | 1 | Apple | | 1 | Make | text | 1 | 2 | 1 | sdfg | | 2 | Year | number | 1 | 1 | 2 | 2009 | | 2 | Year | number | 1 | 2 | 2 | sdfg | | 3 | Type | text | 0 | 1 | 3 | iPhone | | 3 | Type | text | 0 | 2 | 3 | sdfg | | 4 | Axles | text | 0 | 1 | 4 | asdf | | 4 | Axles | text | 0 | 2 | 4 | sdfg | | 7 | Size | text | 0 | 1 | 7 | asd1 | | 7 | Size | text | 0 | 2 | 7 | sdfg | | 8 | Frame | text | 0 | 1 | 8 | | | 8 | Frame | text | 0 | 2 | 8 | sdfg | | 9 | Height | text | 0 | 1 | 9 | | | 9 | Height | text | 0 | 2 | 9 | sdfg | | 10 | Dollies | text | 0 | 1 | 10 | | | 10 | Dollies | text | 0 | 2 | 10 | sdfg | | 11 | Tires/Wheels | text | 0 | 1 | 11 | | | 11 | Tires/Wheels | text | 0 | 2 | 11 | sdfg | | 12 | Condition | text | 1 | 1 | 12 | New | | 12 | Condition | text | 1 | 2 | 12 | sdfg | | 13 | Title | text | 0 | 1 | 13 | | | 13 | Title | text | 0 | 2 | 13 | sdfg | +----+--------------+----------+-----------+------------+--------------+-----------------+ I want to convert it to something more along the lines of: id, Make, Year, Type, Axles, Size, Frame (etc) 1, Apple, 2009, iPhone, ..... 2, sdfg, sdfg, sdfg, ..... Any suggestions?

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  • Moving from NHibernate to FluentNHibernate: assembly error (related to versions)?

    - by goober
    Not sure where to start, but I had gotten the most recent version of NHibernate, successfully mapped the most simple of business objects, etc. When trying to move to FluentNHibernate and do the same thing, I got this error message on build: "System.IO.FileLoadException: Could not load file or assembly 'NHibernate, Version=2.1.0.4000, Culture=neutral, PublicKeyToken=aa95f207798dfdb4' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference." Background: I'm new to Hibernate, NHibernate, and FluentNHibernate -- but not to .NET, C#, etc. Database I have a database table called Category: (PK) CategoryID (type: int), unique, auto-incrementing UserID (type: uniqueidentifier) -- given the value of the user Guid in ASP.NET database Title (type: varchar(50) -- the title of the category Components involved: I have a SessionProviderClass which creates the mapping to the database I have a Category class which has all the virtual methods for FluentNHibernate to override I have a CategoryMap : ClassMap class, which does the fluent mappings for the entity I have a CategoryRepository class that contains the method to add & save the category I have the TestCatAdd.aspx file which uses the CategoryRepository class. Would be happy to post code for any of those, but I'm not sure that it's necessary, as I think the issue is that somewhere there's a version conflict between what FluentNHibernate references and the NHibernate I have installed from before. Thanks in advance for any help you can give!

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  • Best way to get a reasonably random key for MYSQL records

    - by Steve N
    Hi there, I need to generate a reasonably random unique key for a table. It should be something like a GUID for MYSQL. I've tried UUID, but it looks like only the first few characters are actually random- the rest are the same every time I insert them. Essentially, it is desirable for this key field to be very difficult to guess, even if you already have one known value in the column. What is the best way to do this, and how should I set up the field data type to store the value efficiently? Thank you, Steve

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  • Oracle (Old?) Joins - A tool/script for conversion?

    - by Grasper
    I have been porting oracle selects, and I have been running across a lot of queries like so: SELECT e.last_name, d.department_name FROM employees e, departments d WHERE e.department_id(+) = d.department_id; ...and: SELECT last_name, d.department_id FROM employees e, departments d WHERE e.department_id = d.department_id(+); Are there any guides/tutorials for converting all of the variants of the (+) syntax? What is that syntax even called (so I can scour google)? Even better.. Is there a tool/script that will do this conversion for me (Preferred Free)? An optimizer of some sort? I have around 500 of these queries to port.. When was this standard phased out? Any info is appreciated.

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  • Use where condition with unjoined table

    - by Dragos D
    I have the following problem: I am trying to retreive a sum value based on one condition. Problem is that I can't join the conditional value since my tables aren't joined. Here is my syntax: SELECT SUM(value) FROM value v join day d on v.day_id = d.day_id join budget b on d.budget_id = b.budget_id join unit u on v.unit_id = u.unit_id where #output.class = (SELECT distinct s.class FROM sale s where s.id = #output.sale_id) AND u.unit_name in ('electronics') With this sybtax I get no error but neither values. Can you please tell me where I do wrong?

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  • how to use two count or more on one selecting statament ..?

    - by jjj
    i develop this code: SELECT COUNT(NewEmployee.EmployeeID), NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID from my previous two question selecting null stuff and counting issue...that amazing code is working beautifully fine..but now i need to select more than one count... ...searched (google) .... found alias...tried: SELECT COUNT(NewEmployee.EmployeeID) as attenddays, COUNT(NewEmployee.EmployeeID) as empabsent , NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON empabsent =NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3) , attenddays = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID Incorrect syntax near '='. second try: SELECT COUNT(NewEmployee.EmployeeID) as attenddays, COUNT(NewEmployee.EmployeeID) as absentdays, NewEmployee.EmployeeId,EmployeeName FROM NewEmployee INNER JOIN NewTimeAttendance ON attenddays(NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3)) , absentdays(NewEmployee.EmployeeID = NewTimeAttendance.EmployeeID and NewTimeAttendance.TotalTime is null and (NewTimeAttendance.note = '' or NewTimeAttendance.note is null ) and (month=1 or month =2 or month = 3)) GROUP BY NewEmployee.EmployeeID, EmployeeName order by EmployeeID Incorrect syntax near '='. not very good ideas... so ...help thanks in advance

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  • how do i update database using ADODB.Recordset?

    - by every_answer_gets_a_point
    i am using excel to connect to a mysql database: Dim dpath, atime, rtime, lcalib, aname, rname, bstate, instrument As String Dim rs As ADODB.Recordset Set rs = New ADODB.Recordset ConnectDB With wsBooks rs.Open "batchinfo", oConn, adOpenKeyset, adLockOptimistic, adCmdTable Worksheets.Item("Report 1").Select dpath = Trim(Range("B2").Text) atime = Trim(Range("B3").Text) rtime = Trim(Range("B4").Text) lcalib = Trim(Range("B5").Text) aname = Trim(Range("B6").Text) rname = Trim(Range("B7").Text) bstate = Trim(Range("B8").Text) ' instrument = GetInstrFromXML(wbBook.FullName) With rs .AddNew ' create a new record ' add values to each field in the record .Fields("datapath") = dpath .Fields("analysistime") = atime .Fields("reporttime") = rtime .Fields("lastcalib") = lcalib .Fields("analystname") = aname .Fields("reportname") = rname .Fields("batchstate") = "bstate" .Fields("instrument") = "NA" .Update ' stores the new record End With what is the next step? how do i do an rs.execute?

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  • Change Label Control Property Based on Data from SqlDataSource Inside a Repeater

    - by Furqan Muhammad Khan
    I am using a repeater control to populate data from SqlDataSource into my custom designed display-box. <asp:Repeater ID="Repeater1" runat="server" DataSourceID="SqlDataSource1" OnDataBinding="Repeater_ItemDataBound"> <HeaderTemplate> </HeaderTemplate> <ItemTemplate> <div class="bubble-content"> <div style="float: left;"> <h2 class="bubble-content-title"><%# Eval("CommentTitle") %></h2> </div> <div style="text-align: right;"> <asp:Label ID="lbl_category" runat="server" Text=""><%# Eval("CommentType") %> </asp:Label> </div> <div style="float: left;"> <p><%# Eval("CommentContent") %></p> </div> </div> </ItemTemplate> <FooterTemplate> </FooterTemplate> </asp:Repeater> <asp:SqlDataSource ID="mySqlDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:myConnectionString %>" SelectCommand="SELECT [CommentTitle],[CommentType],[CommentContent] FROM [Comments] WHERE ([PostId] = @PostId)"> <SelectParameters> <asp:QueryStringParameter Name="PostId" QueryStringField="id" Type="String" /> </SelectParameters> </asp:SqlDataSource> Now, there can be three types of "CommentTypes" in the database. I want to change the CssClass property of "lbl_category" based on the value of [CommentType]. I tried doing this: <asp:Label ID="lbl_category" runat="server" CssClass="<%# Eval("CommentType") %>" Text=""><%# Eval("CommentType") %></asp:Label> But this gives an error: "The server control is not well formed" and haven't been able to find a way to achieve this in the code behind. Can someone please help?

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  • Wordpress Database SQL query help needed

    - by i-CONICA
    Hi, I've written a PHP script to access the latest item from the wordpress database, which it does. But I need to use it twice, once for the latest item from a specific category, and another from a differerent category... But right now I cannot figure out how to put the query together. The post has a post_parent, which in another table, called wp_term_relationships, is referred to as object_id, and has a term_taxonomy_id, which then relates to a different table, called wp_terms where the term_taxonomy_id is now term_id and then you have the category slug name available to select... I really cannot understand how this query would work though. I've made a really crap mock up of it, to try to "visually" explain what i'm trying to do... SELECT * FROM wp_posts WHERE post_status = 'publish' AND (SELECT term_taxonomy_id FROM wp_term_relationships WHERE object_id = post_parent) AND (SELECT slug FROM wp_terms WHERE term_id = term_taxonomy_id) ORDER BY ID DESC LIMIT 1 Really would appreciate some help... Thanks.

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  • postgres SQL - pg_class question

    - by Sachin Chourasiya
    PostgreSQL stores statistics about tables in the system table called pg_class. The query planner accesses this table for every query. These statistics may only be updated using the analyze command. If the analyze command is not run often, the statistics in this table may not be accurate and the query planner may make poor decisions which can degrade system performance. Another strategy is for the query planner to generate these statistics for each query (including selects, inserts, updates, and deletes). This approach would allow the query planner to have the most up-to-date statistics possible. Why postgres always rely on pg_class instead?

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  • openquery giving differnt results

    - by Mithil Deshmukh
    I have 2 similar queries select * from openquery(powerschool, 'select * from TEACHERS where teachernumber is not null and schoolid=''1050'' and teacherloginid is not null order by teachernumber') and SELECT * from openquery(powerschool, 'SELECT NVL(teachernumber,'''') from TEACHERS where teachernumber is not null and schoolid=''1050'' and teacherloginid is not null order by teachernumber') The first one is giving me 182 rows while the second one gives me 83. What's wrong with the queries?

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  • Is it a Good Practice to Add two Conditions when using a JOIN keyword?

    - by Raúl Roa
    I'd like to know if having to conditionals when using a JOIN keyword is a good practice. I'm trying to filter this resultset by date but I'm unable to get all the branches listed even if there's no expense or income for a date using a WHERE clause. Is there a better way of doing this, if so how? SELECT Branches.Name ,SUM(Expenses.Amount) AS Expenses ,SUM(Incomes.Amount) AS Incomes FROM Branches LEFT JOIN Expenses ON Branches.Id = Expenses.BranchId AND Expenses.Date = '3/11/2010' LEFT JOIN Incomes ON Branches.Id = Incomes.BranchId AND Incomes.Date = '3/11/2010' GROUP BY Branches.Name

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  • How to increase query speed without using full-text search?

    - by andre matos
    This is my simple query; By searching selectnothing I'm sure I'll have no hits. SELECT nome_t FROM myTable WHERE nome_t ILIKE '%selectnothing%'; This is the EXPLAIN ANALYZE VERBOSE Seq Scan on myTable (cost=0.00..15259.04 rows=37 width=29) (actual time=2153.061..2153.061 rows=0 loops=1) Output: nome_t Filter: (nome_t ~~* '%selectnothing%'::text) Total runtime: 2153.116 ms myTable has around 350k rows and the table definition is something like: CREATE TABLE myTable ( nome_t text NOT NULL, ) I have an index on nome_t as stated below: CREATE INDEX idx_m_nome_t ON myTable USING btree (nome_t); Although this is clearly a good candidate for Fulltext search I would like to rule that option out for now. This query is meant to be run from a web application and currently it's taking around 2 seconds which is obviously too much; Is there anything I can do, like using other index methods, to improve the speed of this query?

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  • is there a tool to see the difference between two database tables in mssql?

    - by reinier
    What is a good tool to see the differences between 2 tables (or even better, the datasets returned by 2 queries). EDIT: I'm not interested in the schema changes. Just assume that the schemas are the same. background as to why: I'm porting some legacy code which can fill a database with some pre-calced data. The easiest way to see if I got everything right, is to check the output of the old program, with the new one. I was thinking that if there is some kind of 'diff' tool for databases, this might be great.

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  • Users Hierarchy Logic

    - by user342944
    Hi guys, I am writing a user security module using SQLServer 2008 so threfore need to design a database accordingly. Formally I had Userinfo table with UserID, Username and ParentID to build a recursion and populated tree to represent hierarchy but now I have following criteria which I need to develop. I have now USERS, ADMINISTRATORS and GROUPS. Each node in the user hierarchy is either a user, administrator or group. User Someone who has login access to my application Administrator A user who may also manage all their child user accounts (and their children etc) This may include creating new users and assigning permissions to those users. There is no limit to the number of administrators in user structure. The higher up in the hierarchy that I go administrators have more child accounts to manage which include other child administrators. Group A user account can be designated as a group. This will be an account which is used to group one or more users together so that they can be manage as a unit. But no one can login to my application using a group account. This is how I want to create structure Super Administrator administrator ------------------------------------------------------------- | | | Manager A Manager B Manager C (adminstrator) (administrator) (administrator) | ----------------------------------------- | | | Employee A Employee B Sales Employees (User) (User) (Group) | ------------------------ | | | Emp C Emp D Emp E (User) (User) (User) Now how to build the table structure to achieve this. Do I need to create Users table alongwith Group table or what? Please guide I would really appreciate.

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  • Can MySQL reasonably perform queries on billions of rows?

    - by haxney
    I am planning on storing scans from a mass spectrometer in a MySQL database and would like to know whether storing and analyzing this amount of data is remotely feasible. I know performance varies wildly depending on the environment, but I'm looking for the rough order of magnitude: will queries take 5 days or 5 milliseconds? Input format Each input file contains a single run of the spectrometer; each run is comprised of a set of scans, and each scan has an ordered array of datapoints. There is a bit of metadata, but the majority of the file is comprised of arrays 32- or 64-bit ints or floats. Host system |----------------+-------------------------------| | OS | Windows 2008 64-bit | | MySQL version | 5.5.24 (x86_64) | | CPU | 2x Xeon E5420 (8 cores total) | | RAM | 8GB | | SSD filesystem | 500 GiB | | HDD RAID | 12 TiB | |----------------+-------------------------------| There are some other services running on the server using negligible processor time. File statistics |------------------+--------------| | number of files | ~16,000 | | total size | 1.3 TiB | | min size | 0 bytes | | max size | 12 GiB | | mean | 800 MiB | | median | 500 MiB | | total datapoints | ~200 billion | |------------------+--------------| The total number of datapoints is a very rough estimate. Proposed schema I'm planning on doing things "right" (i.e. normalizing the data like crazy) and so would have a runs table, a spectra table with a foreign key to runs, and a datapoints table with a foreign key to spectra. The 200 Billion datapoint question I am going to be analyzing across multiple spectra and possibly even multiple runs, resulting in queries which could touch millions of rows. Assuming I index everything properly (which is a topic for another question) and am not trying to shuffle hundreds of MiB across the network, is it remotely plausible for MySQL to handle this? UPDATE: additional info The scan data will be coming from files in the XML-based mzML format. The meat of this format is in the <binaryDataArrayList> elements where the data is stored. Each scan produces = 2 <binaryDataArray> elements which, taken together, form a 2-dimensional (or more) array of the form [[123.456, 234.567, ...], ...]. These data are write-once, so update performance and transaction safety are not concerns. My naïve plan for a database schema is: runs table | column name | type | |-------------+-------------| | id | PRIMARY KEY | | start_time | TIMESTAMP | | name | VARCHAR | |-------------+-------------| spectra table | column name | type | |----------------+-------------| | id | PRIMARY KEY | | name | VARCHAR | | index | INT | | spectrum_type | INT | | representation | INT | | run_id | FOREIGN KEY | |----------------+-------------| datapoints table | column name | type | |-------------+-------------| | id | PRIMARY KEY | | spectrum_id | FOREIGN KEY | | mz | DOUBLE | | num_counts | DOUBLE | | index | INT | |-------------+-------------| Is this reasonable?

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