Search Results

Search found 8340 results on 334 pages for 'merge join'.

Page 157/334 | < Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164  | Next Page >

  • MySQL to PostreSQL and Named Scope

    - by Lowgain
    I've got a named scope for one of my models that works fine. The code is: named_scope :inbox_threads, lambda { |user| { :include => [:deletion_flags, :recipiences], :conditions => ["recipiences.user_id = ? AND deletion_flags.user_id IS NULL", user.id], :group => "msg_threads.id" }} This works fine on my local copy of the app with a MySQL database, but when I push my app to Heroku (which only uses PostgreSQL), I get the following error: ActiveRecord::StatementInvalid (PGError: ERROR: column "msg_threads.subject" must appear in the GROUP BY clause or be used in an aggregate function: SELECT "msg_threads"."id" AS t0_r0, "msg_threads"."subject" AS t0_r1, "msg_threads"."originator_id" AS t0_r2, "msg_thr eads"."created_at" AS t0_r3, "msg_threads"."updated_at" AS t0_r4, "msg_threads"."url_key" AS t0_r5, "deletion_flags"."id" AS t1_r0, "deletion_flags"."user_id" AS t1_r1, "deletion_flags"."msg_thread_id" AS t1_r2, "deletion_flags"."confirmed" AS t1_r3, "deletion_flags"."created_at" AS t1_r4, "deletion_flags"."updated_at" AS t1_r5, "recipiences"."id" AS t2_r0, "recipiences"."user_id" AS t2_r1, "recipiences"."msg_thread_id" AS t2_r2, "recipiences"."created_at" AS t2_r3, "recipien ces"."updated_at" AS t2_r4 FROM "msg_threads" LEFT OUTER JOIN "deletion_flags" ON deletion_flags.msg_thread_id = msg_threads.id LEFT OUTER JOIN "recipiences" ON recipiences.msg_thread_id = msg_threads.id WHERE (recipiences.user_id = 1 AND deletion_flags.user_id IS NULL) GROUP BY msg_threads.id) I'm not as familiar with the working of Postgres, so what would I need to add here to get this working? Thanks!

    Read the article

  • Learn Prolog Now! DCG Practice Example

    - by Timothy
    I have been progressing through Learn Prolog Now! as self-study and am now learning about Definite Clause Grammars. I am having some difficulty with one of the Practical Session's tasks. The task reads: The formal language anb2mc2mdn consists of all strings of the following form: an unbroken block of as followed by an unbroken block of bs followed by an unbroken block of cs followed by an unbroken block of ds, such that the a and d blocks are exactly the same length, and the c and d blocks are also exactly the same length and furthermore consist of an even number of cs and ds respectively. For example, ε, abbccd, and aaabbbbccccddd all belong to anb2mc2mdn. Write a DCG that generates this language. I am able to write rules that generate andn, b2mc2m, and even anb2m and c2mndn... but I can't seem to join all these rules into anb2mc2mdn. The following are my rules that can generate andn and b2mc2m. s1 --> []. s1 --> a,s1,d. a --> [a]. d --> [d]. s2 --> []. s2 --> c,c,s2,d,d. c --> [c]. d --> [d]. Is anb2mc2mdn really a CFG, and is it possible to write a DCG using only what was taught in the lesson (no additional arguments or code, etc)? If so, can anyone offer me some guidance how I can join these so that I can solve the given task?

    Read the article

  • SELECT SUM PHP MySQL problem

    - by user345426
    This is driving me nuts! Below you will find my PHP/MySQL code but I will post the direct mySQL statement here: SELECT SUM( ot.value ) AS msa FROM orders o LEFT JOIN orders_total ot ON ot.orders_id = o.orders_id WHERE ot.class = 'ot_total' AND UNIX_TIMESTAMP( o.date_purchased ) >=1262332800 AND UNIX_TIMESTAMP( o.date_purchased ) <=1264924800 AND o.sales_rep_id = '2' When I execute this statement inside of phpMyAdmin I get the sum for ot.value which is associated to "msa". Although, when I run my php code it does not return a value. Anyone see the problem? // works in phpMyAdmin but not displaying during PHP execution! $monthly_sales_amount_sql = "SELECT SUM(ot.value) AS msa FROM orders o LEFT JOIN orders_total ot ON ot.orders_id = o.orders_id WHERE ot.class = 'ot_total' AND UNIX_TIMESTAMP(o.date_purchased) >= $start_timestamp AND UNIX_TIMESTAMP(o.date_purchased) <= $end_timestamp AND o.sales_rep_id = '" . $sales_rep_id "'"; $result = mysql_query($monthly_sales_amount_sql); $row = mysql_fetch_assoc($result); echo "MSA: " . $row['msa'] . "<BR><BR>";

    Read the article

  • Are there any security issues to avoid when providing a either-email-or-username-can-act-as-username

    - by Tchalvak
    I am in the process of moving from a "username/password" system to one that uses email for login. I don't think that there's any horrible problem with allowing either email or username for login, and I remember seeing sites that I consider somewhat respectable doing it as well, but I'd like to be aware of any major security flaws that I may be introducing. More specifically, here is the pertinent function (the query_row function parameterizes the sql). function authenticate($p_user, $p_pass) { $user = (string)$p_user; $pass = (string)$p_pass; $returnValue = false; if ($user != '' && $pass != '') { // Allow login via username or email. $sql = "SELECT account_id, account_identity, uname, player_id FROM accounts join account_players on account_id=_account_id join players on player_id = _player_id WHERE lower(account_identity) = lower(:login) OR lower(uname) = lower(:login) AND phash = crypt(:pass, phash)"; $returnValue = query_row($sql, array(':login'=>$user, ':pass'=>$pass)); } return $returnValue; } Notably, I have added the WHERE lower(account_identity) = lower(:login) OR lower(uname) = lower(:login) ...etc section to allow graceful backwards compatibility for users who won't be used to using their email for the login procedure. I'm not completely sure that that OR is safe, though. Are there some ways that I should tighten the security of the php code above?

    Read the article

  • Data historian queries

    - by Scott Dennis
    Hi, I have a table that contains data for electric motors the format is: DATE(DateTime) | TagName(VarChar(50) | Val(Float) | 2009-11-03 17:44:13.000 | Motor_1 | 123.45 2009-11-04 17:44:13.000 | Motor_1 | 124.45 2009-11-05 17:44:13.000 | Motor_1 | 125.45 2009-11-03 17:44:13.000 | Motor_2 | 223.45 2009-11-04 17:44:13.000 | Motor_2 | 224.45 Data for each motor is inserted daily, so there would be 31 Motor_1s and 31 Motor_2s etc. We do this so we can trend it on our control system displays. I am using views to extract last months max val and last months min val. Same for this months data. Then I join the two and calculate the difference to get the actual run hours for that month. The "Val" is a nonresetable Accumulation from a PLC(Controller). This is my query for Last months Max Value: SELECT TagName, Val AS Hours FROM dbo.All_Data_From_Last_Mon AS cur WHERE (NOT EXISTS (SELECT TagName, Val FROM dbo.All_Data_From_Last_Mon AS high WHERE (TagName = cur.TagName) AND (Val > cur.Val))) This is my query for Last months Max Value: SELECT TagName, Val AS Hours FROM dbo.All_Data_From_Last_Mon AS cur WHERE (NOT EXISTS (SELECT TagName, Val FROM dbo.All_Data_From_Last_Mon AS high WHERE (TagName = cur.TagName) AND (Val < cur.Val))) This is the query that calculates the difference and runs a bit slow: SELECT dbo.Motors_Last_Mon_Max.TagName, STR(dbo.Motors_Last_Mon_Max.Hours - dbo.Motors_Last_Mon_Min.Hours, 12, 2) AS Hours FROM dbo.Motors_Last_Mon_Min RIGHT OUTER JOIN dbo.Motors_Last_Mon_Max ON dbo.Motors_Last_Mon_Min.TagName = dbo.Motors_Last_Mon_Max.TagName I know there is a better way. Ultimately I just need last months total and this months total. Any help would be appreciated. Thanks in advance

    Read the article

  • MySQL - What is wrong with this query or my database? Terrible performance.

    - by Moss
    SELECT * from `employees` a LEFT JOIN (SELECT phone1 p1, count(*) c, FROM `employees` GROUP BY phone1) b ON a.phone1 = b.p1; I'm not sure if it is this query in particular that has the problem. I have been getting terrible performance in general with this database. The table in question has 120,000 rows. I have tried this particular query remotely and locally with the MyISAM and InnoDB engines, with different types of joins, and with and without an index on phone1. I can get this to complete in about 4 minutes on a 10,000 row table successfully but performance drops exponentially with larger tables. Remotely it will lose connection to the server and locally it brings my system to its knees and seems to go on forever. This query is only a smaller step I was trying to do when a larger query couldn't complete. Maybe I should explain the whole scenario. I have one big flat ugly table that lists a bunch of people and their contact info and the info of the companies they work for. I'm trying to normalize the database and intelligently determine which phone numbers apply to individual people and which apply to an office location. My reasoning is that if a phone number occurs multiple times and the number of occurrence equals the number of times that the street address it is attached to occurs then it must be an office number. So the first step is to count each phone number grouping by phone number. Normally if you just use COUNT()...GROUP BY it will only list the first record it finds in that group so I figured I have to join the full table to the count table where the phone number matches. This does work but as I said I can't successfully complete it on any table much larger than 10,000 rows. This seems pathetic and this doesn't seem like a crazy query to do. Is there a better way to achieve what I want or do I have to break my large table into 12 pieces or is there something wrong with the table or db?

    Read the article

  • Selecting random top 3 listings per shop for a range of active advertising shops

    - by GraGra33
    I’m trying to display a list of shops each with 3 random items from their shop, if they have 3 or more listings, that are actively advertising. I have 3 tables: one for the shops – “Shops”, one for the listings – “Listings” and one that tracks active advertisers – “AdShops”. Using the below statement, the listings returned are random however I’m not getting exactly 3 listings (rows) returned per shop. SELECT AdShops.ID, Shops.url, Shops.image_url, Shops.user_name AS shop_name, Shops.title, L.listing_id AS listing_id, L.title AS listing_title, L.price as price, L.image_url AS listing_image_url, L.url AS listing_url FROM AdShops INNER JOIN Shops ON AdShops.user_id = Shops.user_id INNER JOIN Listings AS L ON Shops.user_id = L.user_id WHERE (Shops.is_vacation = 0 AND Shops.listing_count > 2 AND L.listing_id IN (SELECT TOP 3 L2.listing_id FROM Listings AS L2 WHERE L2.listing_id IN (SELECT TOP 100 PERCENT L3.listing_id FROM Listings AS L3 WHERE (L3.user_id = L.user_id) ) ORDER BY NEWID() ) ) ORDER BY Shops.shop_name I’m stumped. Anyone have any ideas on how to fix it? The ideal solution would be one record per store with the 3 listings (and associated data) were in columns and not rows – is this possible?

    Read the article

  • How to optimize a postgreSQL server for a "write once, read many"-type infrastructure ?

    - by mhu
    Greetings, I am working on a piece of software that logs entries (and related tagging) in a PostgreSQL database for storage and retrieval. We never update any data once it has been inserted; we might remove it when the entry gets too old, but this is done at most once a day. Stored entries can be retrieved by users. The insertion of new entries can happen rather fast and regularly, thus the database will commonly hold several millions elements. The tables used are pretty simple : one table for ids, raw content and insertion date; and one table storing tags and their values associated to an id. User search mostly concern tags values, so SELECTs usually consist of JOIN queries on ids on the two tables. To sum it up : 2 tables Lots of INSERT no UPDATE some DELETE, once a day at most some user-generated SELECT with JOIN huge data set What would an optimal server configuration (software and hardware, I assume for example that RAID10 could help) be for my PostgreSQL server, given these requirements ? By optimal, I mean one that allows SELECT queries taking a reasonably little amount of time. I can provide more information about the current setup (like tables, indexes ...) if needed.

    Read the article

  • many to many relationship mysql select

    - by zeina
    Let's consider 2 tables "schools" and "students". Now a student may belong to different schools in his life, and a school have many students. So this is a many to many example. A third table "links" specify the relation between student and school. Now to query this I do the following: Select sc.sid , -- stands for school id st.uid, -- stands for student id sc.sname, -- stands for school name st.uname, -- stands for student name -- select more data about the student joining other tables for that from students s left join links l on l.uid=st.uid -- l.uid stands for the student id on the links table left join schools sc on sc.sid=l.sid -- l.sid is the id of the school in the links table where st.uid=3 -- 3 is an example this query will return duplicate data for the user id if he has more than one school, so to fix this I added group by st.uid, yet I also need the list of school name related to the same user. Is there a way to do it with fixing the query I wrote instead of having 2 queries? So as example I want to have Luci of schools ( X, Y, Z, R, ...) etc

    Read the article

  • Fastest way to become a MySQL expert?

    - by Kerry
    I have been using MySQL for years, mainly on smaller projects until the last year or so. I'm not sure if it's the nature of the language or my lack of real tutorials that gives me the feeling of being unsure if what I'm writing is the proper way for optimization purposes and scaling purposes. While self-taught in PHP I'm very sure of myself and the code I write, easily can compare it to others and so on. With MySQL, I'm not sure whether (and in what cases) an INNER JOIN or LEFT JOIN should be used, nor am I aware of the large amount of functionality that it has. While I've written code for databases that handled tens of millions of records, I don't know if it's optimum. I often find that a small tweak will make a query take less than 1/10 of the original time... but how do I know that my current query isn't also slow? I would like to become completely confident in this field in the ability to optimize databases and be scalable. Use is not a problem -- I use it on a daily basis in a number of different ways. So, the question is, what's the path? Reading a book? Website/tutorials? Recommendations?

    Read the article

  • How to work with CTE. There is some error related to anchor.

    - by Shantanu Gupta
    I am creating a hierarchy representaion of a column. But an error occurs Details are Msg 240, Level 16, State 1, Line 1 Types don't match between the anchor and the recursive part in column "DISPLAY" of recursive query "CTE". I know there is some typecasting error. But I dont know how to remove error. Please just dont only sort out my error. I need explanation why this error is coming. When this error occurs. I am trying to sort table on the basis of sort col that i m introducing. I want to add '-' at every level and want to sort accordingly. Please help WITH CTE (PK_CATEGORY_ID, [DESCRIPTION], FK_CATEGORY_ID, DISPLAY, SORT, DEPTH) AS ( SELECT PK_CATEGORY_ID, [DESCRIPTION], FK_CATEGORY_ID, '-' AS DISPLAY, '--' AS SORT, 0 AS DEPTH FROM dbo.L_CATEGORY_TYPE WHERE FK_CATEGORY_ID IS NULL UNION ALL SELECT T.PK_CATEGORY_ID, T.[DESCRIPTION], T.FK_CATEGORY_ID, CAST(DISPLAY+T.[DESCRIPTION] AS VARCHAR(1000)), '--' AS SORT, C.DEPTH +1 FROM dbo.L_CATEGORY_TYPE T JOIN CTE C ON C.PK_CATEGORY_ID = T.FK_CATEGORY_ID --SELECT T.PK_CATEGORY_ID, C.SORT+T.[DESCRIPTION], T.FK_CATEGORY_ID --, CAST('--' + C.SORT AS VARCHAR(1000)) AS SORT, CAST(DEPTH +1 AS INT) AS DEPTH --FROM dbo.L_CATEGORY_TYPE T JOIN CTE C ON C.FK_CATEGORY_ID = T.PK_CATEGORY_ID ) SELECT PK_CATEGORY_ID, [DESCRIPTION], FK_CATEGORY_ID, DISPLAY, SORT, DEPTH FROM CTE ORDER BY SORT

    Read the article

  • How do I strip multiple (optional) parts of a SQL string using .NET Regular Expressions?

    - by Luc
    I've been working on this for a few hours now and can't find any help on it. Basically, I'm trying to strip a SQL string into various parts (fields, from, where, having, groupBy, orderBy). I refuse to believe that I'm the first person to ever try to do this, so I'd like to ask for some advise from the StackOverflow community. :) To understand what I need, assume the following SQL string: select * from table1 inner join table2 on table1.id = table2.id where field1 = 'sam' having table1.field3 > 0 group by table1.field4 order by table1.field5 I created a regular expression to group the parts accordingly: select\s+(?<fields>.+)\s+from\s+(?<from>.+)\s+where\s+(?<where>.+)\s+having\s+(?<having>.+)\s+group\sby\s+(?<groupby>.+)\s+order\sby\s+(?<orderby>.+) This gives me the following results: fields => * from => table1 inner join table2 on table1.id = table2.id where => field1 = 'sam' having => table1.field3 > 0 groupby => table1.field4 orderby => table1.field5 The problem that I'm faced with is that if any part of the SQL string is missing after the 'from' clause, the regular expression doesn't match. To fix that, I've tried putting each optional part in it's own (...)? group but that doesn't work. It simply put all the optional parts (where, having, groupBy, and orderBy) into the 'from' group. Any ideas?

    Read the article

  • Is there an efficient way in LINQ to use a contains match if and only if there is no exact match?

    - by Peter
    I have an application where I am taking a large number of 'product names' input by a user and retrieving some information about each product. The problem is, the user may input a partial name or even a wrong name, so I want to return the closest matches for further selection. Essentially if product name A exactly matches a record, return that, otherwise return any contains matches. Otherwise return null. I have done this with three separate statements, and I was wondering if there was a more efficient way to do this. I am using LINQ to EF, but I materialize the products to a list first for performance reasons. productNames is a List of product names (input by the user). products is a List of product 'records' var directMatches = (from s in productNames join p in products on s.ToLower() equals p.name.ToLower() into result from r in result.DefaultIfEmpty() select new {Key = s, Product = r}); var containsMatches = (from d in directMatches from p in products where d.Product == null && p.name.ToLower().Contains(d.Key) select new { d.Key, Product = p }); var matches = from d in directMatches join c in containsMatches on d.Key equals c.Key into result from r in result.DefaultIfEmpty() select new {d.Key, Product = d.Product ?? (r != null ? r.Product: null) };

    Read the article

  • Get the first and last posts in a thread

    - by Grampa
    I am trying to code a forum website and I want to display a list of threads. Each thread should be accompanied by info about the first post (the "head" of the thread) as well as the last. My current database structure is the following: threads table: id - int, PK, not NULL, auto-increment name - varchar(255) posts table: id - int, PK, not NULL, auto-increment thread_id - FK for threads The tables have other fields as well, but they are not relevant for the query. I am interested in querying threads and somehow JOINing with posts so that I obtain both the first and last post for each thread in a single query (with no subqueries). So far I am able to do it using multiple queries, and I have defined the first post as being: SELECT * FROM threads t LEFT JOIN posts p ON t.id = p.thread_id ORDER BY p.id LIMIT 0, 1 The last post is pretty much the same except for ORDER BY id DESC. Now, I could select multiple threads with their first or last posts, by doing: SELECT * FROM threads t LEFT JOIN posts p ON t.id = p.thread_id ORDER BY p.id GROUP BY t.id But of course I can't get both at once, since I would need to sort both ASC and DESC at the same time. What is the solution here? Is it even possible to use a single query? Is there any way I could change the structure of my tables to facilitate this? If this is not doable, then what tips could you give me to improve the query performance in this particular situation?

    Read the article

  • System Error when running PyQt4's loadUi()

    - by user633804
    Hello, I'm pretty new to Qt, Python and their combinations. I'm currently writing a QGIS plugin in python (I used QtCreator 2.1 (Qt Designer 4.7) to generate a .ui-file and am now trying to use it for a Quantum GIS plugin that's written in Python 2.5 (and running in the Quantum GIS Python 2.5 console)). I am running into trouble when loading the ui-file dynamically when the program runs the loadUi() function. What throws me off is that the error occurs outside my script. Does that mean, I'm passing something wrong into it? Where does the error come in? Any hints on what could be wrong? code_dir = os.path.dirname(os.path.abspath(__file__)) self.ui = loadUi(os.path.join(code_dir, "Ui_myfile.ui"), self) This is the Error Code I am getting (minus the first paragraph): File "C:/Dokumente und Einstellungen/name.name/.qgis/python/plugins\myfile\myfile_gui.py", line 42, in __ init __ self.ui = loadUi(os.path.join(code_dir, "Ui_myfile.ui"), self) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic__init__.py", line 112, in loadUi return DynamicUILoader().loadUi(uifile, baseinstance) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\Loader\loader.py", line 21, in loadUi return self.parse(filename) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\uiparser.py", line 768, in parse actor(elem) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\uiparser.py", line 616, in createUserInterface self.traverseWidgetTree(elem) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\uiparser.py", line 594, in traverseWidgetTree handler(self, child) File "C:\PROGRA~1\QUANTU~1\apps\Python25\lib\site-packages\PyQt4\uic\uiparser.py", line 233, in createWidget topwidget.setCentralWidget(widget) SystemError: error return without exception set

    Read the article

  • SQL problem - select accross multiple tables (user groups)

    - by morpheous
    I have a db schema which looks something like this: create table user (id int, name varchar(32)); create table group (id int, name varchar(32)); create table group_member (foobar_id int, user_id int, flag int); I want to write a query that allows me to so the following: Given a valid user id (UID), fetch the ids of all users that are in the same group as the specified user id (UID) AND have group_member.flag=3. Rather than just have the SQL. I want to learn how to think like a Db programmer. As a coder, SQL is my weakest link (since I am far more comfortable with imperative languages than declarative ones) - but I want to change that. Anyway here are the steps I have identified as necessary to break down the task. I would be grateful if some SQL guru can demonstrate the simple SQL statements - i.e. atomic SQL statements, one for each of the identified subtasks below, and then finally, how I can combine those statements to make the ONE statement that implements the required functionality. Here goes (assume specified user_id [UID] = 1): //Subtask #1. Fetch list of all groups of which I am a member Select group.id from user inner join group_member where user.id=group_member.user_id and user.id=1 //Subtask #2 Fetch a list of all members who are members of the groups I am a member of (i.e. groups in subtask #1) Not sure about this ... select user.id from user, group_member gm1, group_member gm2, ... [Stuck] //Subtask #3 Get list of users that satisfy criteria group_member.flag=3 Select user.id from user inner join group_member where user.id=group_member.user_id and user.id=1 and group_member.flag=3 Once I have the SQL for subtask2, I'd then like to see how the complete SQL statement is built from these subtasks (you dont have to use the SQL in the subtask, it just a way of explaining the steps involved - also, my SQL may be incorrect/inefficient, if so, please feel free to correct it, and point out what was wrong with it). Thanks

    Read the article

  • Need a refresher course on property access...

    - by Code Sherpa
    Hi. I need help with accessing class properties within a given class. For example, take the below class: public partial class Account { private Profile _profile; private Email _email; private HostInfo _hostInfo; public Profile Profile { get { return _profile; } set { _profile = value; } } public Email Email { get { return _email; } set { _email = value; } } public HostInfo HostInfo { get { return _hostInfo; } set { _hostInfo = value; } } In the class "Account" exists a bunch of class properties such as Email or Profile. Now, when I want to access those properties at run-time, I do something like this (for Email): _accountRepository = ObjectFactory.GetInstance<IAccountRepository>(); string username = Cryptography.Decrypt(_webContext.UserNameToVerify, "verify"); Account account = _accountRepository.GetAccountByUserName(username); if(account != null) { account.Email.IsConfirmed = true; But, I get "Object reference not set..." for account.Email... Why is that? How do I access Account such that account.Email, account.Profile, and so on returns the correct data for a given AccountId or UserName. Here is a method that returns Account: public Account GetAccountByUserName(string userName) { Account account = null; using (MyDataContext dc = _conn.GetContext()) { try { account = (from a in dc.Accounts where a.UserName == userName select a).FirstOrDefault(); } catch { //oops } } return account; } The above works but when I try: account = (from a in dc.Accounts join em in dc.Emails on a.AccountId equals em.AccountId join p in dc.Profiles on em.AccountId equals p.AccountId where a.UserName == userName select a).FirstOrDefault(); I am still getting object reference exceptions for my Email and Profile properties. Is this simply a SQL problem or is there something else I need to be doing to be able to fully access all the properties within my Account class? Thanks!

    Read the article

  • MySQL: SELECT highest column value when WHERE finds similar entries

    - by Ike
    My question is comparable to this one, but not quite the same. I have a database with a huge amount of books, with different editions of some of the same book titles. I'm looking for an SQL statement giving me the highest edition number of each of the titles I'm selecting with a WHERE clause (to find specific book series). Here's what the table looks like: |id|title |edition|year| |--|-------------------------|-------|----| |01|Serie One Title One |1 |2007| |02|Serie One Title One |2 |2008| |03|Serie One Title One |3 |2009| |04|Serie One Title Two |1 |2001| |05|Serie One Title Three |1 |2008| |06|Serie One Title Three |2 |2009| |07|Serie One Title Three |3 |2010| |08|Serie One Title Three |4 |2011| |--|-------------------------|-------|----| The result I'm looking for is this: |id|title |edition|year| |--|-------------------------|-------|----| |03|Serie One Title One |3 |2009| |04|Serie One Title Two |1 |2001| |08|Serie One Title Three |4 |2011| |--|-------------------------|-------|----| The closest I got was using this statement: select id, title, max(edition), max(year) from books where title like "serie one%" group by name; but it returns the highest edition and year and includes the first id it finds: |--|-----------------------|-------|----| |01|Serie One Title One |3 |2009| |04|Serie One Title Two |1 |2001| |05|Serie One Title Three |4 |2011| |--|-----------------------|-------|----| This fancy join also comes close, but doesn't give the right result: select b.id, b.title, b.edition, b.year from books b inner join (select name, max(edition) as maxedition from books group by title) g on b.edition = g.maxedition where b.title like "serie one%" group by title; Using this I'm getting unique titles, but mostly old editions.

    Read the article

  • Javascript nested functions not returning

    - by Achintha Samindika
    I'm building a phonehap application. I'm using an web sql and everything works fine till data retival. function getItemGroups(){ var items_groups = new Array(); var db = window.openDatabase("merbokDB", "1.0", "MerbokDB", 5232394); db.transaction( function(tx){ tx.executeSql('SELECT * FROM item_groups',[], function(tx,result){ if(result.rows.length > 0){ var len = result.rows.length; for (var i=0; i<len; i++){ items_groups.push(result.rows.item(i).item_group); } console.log(items_groups.join()); } } ,errorCB); }, errorCB); return items_groups; } var myproducts = getItemGroups(); My problem was when I run the code "myproducts" variable is blank. but the I can see console.log(items_groups.join()); following line printing the values in console. Is I'm wrong in the way I returning?

    Read the article

  • SQL Server 2008 - Full Text Query

    - by user208662
    Hello, I have two tables in a SQL Server 2008 database in my company. The first table represents the products that my company sells. The second table contains the product manufacturer’s details. These tables are defined as follows: Product ------- ID Name ManufacturerID Description Manufacturer ------------ ID Name As you can imagine, I want to make this as easy as possible for our customers to query this data. However, I’m having problems writing a forgiving, yet powerful search query. For instance, I’m anticipating people to search based on phonetical spellings. Because of this, the data may not match the exact data in my database. In addition, I think some individuals will search by manufacturer’s name first, but I want the matching product names to appear first. Based on these requirements, I’m currently working on the following query: select p.Name as 'ProductName', m.Name as 'Manufacturer', r.Rank as 'Rank' from Product p inner join Manufacturer m on p.ManufacturerID=m.ID inner join CONTAINSTABLE(Product, Name, @searchQuery) as r Oddly, this query is throwing an error. However, I have no idea why. Squiggles appear to the right of the last parenthesis in management studio. The tool tip says "An expression of non-boolean type specified in a context where a condition is expected". I understand what this statement means. However, I guess I do not know how COntainsTable works. What am I doing wrong? Thank you

    Read the article

  • Fix N+1 query in "declarative_authorization" gem using gem "bullet"

    - by makaroni4
    Currently I am working on one big web application and to make it work faster I decided to refactor all N+1 queries (to decrease number of requests to database, http://rails-bestpractices.com/posts/29-fix-n-1-queries). So I installed gem "bullet" which doesn`t work with Rails 3.1.1 now (you can use fork from https://github.com/flyerhzm/bullet). When using declarative_authorization gem on each page I get same alerts: N+1 Query detected Role => [:permissions] Add to your finder: :include => [:permissions] N+1 Query detected Permission => [:permission_rules] Add to your finder: :include => [:permission_rules] CACHE (0.0ms) SELECT "roles".* FROM "roles" CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 1 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 2 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 3 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 4 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 6 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 7 CACHE (0.0ms) SELECT "permissions".* FROM "permissions" WHERE "permissions"."role_id" = 8 CACHE (0.0ms) SELECT "permission_rules".* FROM "permission_rules" INNER JOIN "permission_rules_permissions" ON "permission_rules"."id" = "permission_rules_permissions"."permission_rule_id" WHERE "permission_rules_permissions"."permission_id" = 30 CACHE (0.0ms) SELECT "permission_rules".* FROM "permission_rules" INNER JOIN "permission_rules_permissions" ON "permission_rules"."id" = "permission_rules_permissions"."permission_rule_id" WHERE "permission_rules_permissions"."permission_id" = 31 ... Could you please help me with that and to make this queries faster?

    Read the article

  • Copy SQL From Access To Delphi Script

    - by Libra
    I found a difficult with SQL on Delphi, I use ADOconnection and ADOQuery. Here these Query With ADOQuery Do Begin SQL.Text:='SELECT QUnionSAPiutang.kd_Customer, T_Customer.nama_customer, ' +'CDbl(IIf(IsNull(DSum("SA","QSumSAPiutang","kd_Customer='" & [QUnionSAPiutang].[kd_Customer] & "' AND ' +'Tgl<#1/1/2010# ")),0,DSum("SA","QSumSAPiutang","kd_Customer='" & [QUnionSAPiutang].[kd_Customer] & "' ' +'AND Tgl<#1/1/2010# "))) AS SA1, Sum(QUnionSAPiutang.D) AS Debit, Sum(QUnionSAPiutang.K) AS Kredit, ' +'[SA1]+[Debit]-[Kredit] AS SAkh ' +'FROM QUnionSAPiutang INNER JOIN T_Customer ON ' +'QUnionSAPiutang.kd_Customer = T_Customer.kd_customer ' +'WHERE (((QUnionSAPiutang.Tgl) Between #1/1/2010# And #1/31/2010#)) ' +'GROUP BY QUnionSAPiutang.kd_Customer, T_Customer.nama_customer'; End That Query Above has an error.... I try to fix, but still have an error. I hope you can help my problem, please fix that Query. I use Ms.Access XP for Database, if I run that Query on Accsess, the error is nothing. I use three object T_Customer, QUnionSAPiutang, and QSumSAPiutang. Where the red text is a part of QSumSAPiutang. coz QSumSAPiutang not directly Join with the others, it is call with DSum. Please help me, Thank you for your time. I hope reply from you soon....

    Read the article

  • SQL with HAVING and temp table not working in Rails

    - by chrisrbailey
    I can't get the following SQL query to work quite right in Rails. It runs, but it fails to do the "HAVING row_number = 1" part, so I'm getting all the records, instead of just the first record from each group. A quick description of the query: it is finding hotel deals with various criteria, and in particular, priortizing them being paid, and then picking the one with the highest dealrank. So, if there are paid deal(s), it'll take the highest one of those (by dealrank) first, if no paid deals, it takes the highest dealrank unpaid deal for each hotel. Using MAX(dealrank) or something similar does not work as a way to pick off the first row of each hotel group, which is why I have the enclosing temptable and the creation of the row_number column. Here's the query: SELECT *, @num := if(@hid = hotel_id, @num + 1, 1) as row_number, @hid := hotel_id as dummy FROM ( SELECT hotel_deals.*, affiliates.cpc, (CASE when affiliates.cpc 0 then 1 else 0 end) AS paid FROM hotel_deals INNER JOIN hotels ON hotels.id = hotel_deals.hotel_id LEFT OUTER JOIN affiliates ON affiliates.id = hotel_deals.affiliate_id WHERE ((hotel_deals.percent_savings = 0) AND (hotel_deals.booking_deadline = ?)) GROUP BY hotel_deals.hotel_id, paid DESC, hotel_deals.dealrank ASC) temptable HAVING row_number = 1 I'm currently using Rails' find_by_sql to do this, although I've also tried putting it into a regular find using the :select, :from, and :having parts (but :having won't get used unless you have a :group as well). If there is a different way to write this query, that'd be good to know too. I am using Rails 2.3.5, MySQL 5.0.x.

    Read the article

  • Python parsing error message functions

    - by user1716168
    The code below was created by me with the help of many SO veterans: The code takes an entered math expression and splits it into operators and operands for later use. I have created two functions, the parsing function that splits, and the error function. I am having problems with the error function because it won't display my error messages and I feel the function is being ignored when the code runs. An error should print if an expression such as this is entered: 3//3+4,etc. where there are two operators together, or there are more than two operators in the expression overall, but the error messages dont print. My code is below: def errors(): numExtrapolation,opExtrapolation=parse(expression) if (len(numExtrapolation) == 3) and (len(opExtrapolation) !=2): print("Bad1") if (len(numExtrapolation) ==2) and (len(opExtrapolation) !=1): print("Bad2") def parse(expression): operators= set("*/+-") opExtrapolate= [] numExtrapolate= [] buff=[] for i in expression: if i in operators: numExtrapolate.append(''.join(buff)) buff= [] opExtrapolate.append(i) opExtrapolation=opExtrapolate else: buff.append(i) numExtrapolate.append(''.join(buff)) numExtrapolation=numExtrapolate #just some debugging print statements print(numExtrapolation) print("z:", len(opExtrapolation)) return numExtrapolation, opExtrapolation errors() Any help would be appreciated. Please don't introduce new code that is any more advanced than the code already here. I am looking for a solution to my problem... not large new code segments. Thanks.

    Read the article

  • T-SQL: how to sort table rows based on 2 columns

    - by Criss Nautilus
    I'm quite stuck with this problem for sometime now.. How do I sort column A depending on the contents of Column B? I have this sample: ID count columnA ColumnB 12 1 A B 13 2 C D 14 3 B C I want to sort it like this: ID count ColumnA ColumnB 12 1 A B 14 3 B C 13 2 C D so I need to sort the rows if the previous row of ColumnB = the next row of ColumnA I'm thinking a loop? but can't quite imagine how it will work... I was thinking it will go like this (maybe) SELECT a.ID, a.ColumnA, a.ColumnB FROM TableA WITH a (NOLOCK) LEFT JOIN TableA b WITH (NOLOCK) ON a.ID = b.ID and a.counts = b.counts Where a.columnB = b.ColumnA the above code isn't working though and I was thinking more on the lines of... DECLARE @counts int = 1 DECLARE @done int = 0 --WHILE @done = 0 BEGIN SELECT a.ID, a.ColumnA, a.ColumnB FROM TableA WITH a (NOLOCK) LEFT JOIN TableA b WITH (NOLOCK) ON a.ID = b.ID and a.counts = @counts Where a.columnB = b.ColumnA set @count = @count +1 END If this was a C code, would be easier for me but t-sql's syntax is making it a bit harder for a noobie like me.

    Read the article

< Previous Page | 153 154 155 156 157 158 159 160 161 162 163 164  | Next Page >