![]() ![]() ![]() ![]() tables The tables that you wish to retrieve records from. Since this was originally tagged just SQL (no SQLite). Syntax The syntax for the ORDER BY clause in SQLite is: SELECT expressions FROM tables WHERE conditions ORDER BY expression ASC DESC Parameters or Arguments expressions The columns or calculations that you wish to retrieve. Here's a closely related answer with more detailed examples: If you want to filter for a particular CID, just add AND "CID" = 'C1' or whatever to the outer WHERE clause. Output (PostgreSQL): ROWID | CID | PID | Score | SortKey SQLite demo showing it works just fine on the SQLite3 command line: MySQL 5.5 (fails two ways MySQL doesn't like a."ROWID" quoting even in ANSI mode so I had to un-quote then it fails with This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery): !2/e1f31/2 SQLite3 (works fine, same query text, but needed single-valued inserts due to apparent JDBC driver limitation): !7/9ecd8/1 It won't work on MySQL 5.5 or the latest 5.6 milestone because MySQL doesn't support LIMIT in a subquery used with IN. column WHERE constraintexpression GROUP BY column HAVING constraintexpression ORDER BY column ASC/DESC LIMIT count OFFSET COUNT. Lets try age: SELECTsex,age,nameFROMpeopleORDERBYageLIMIT3 Where does ORDER BY fit How to remember where ORDER BYfits in the query syntax so far Well, we know that LIMITwill be the last part of virtually any statement. I tested the above in PostgreSQL 9.2 and in SQLite3 3.7.11 it works fine in both. The most basic usage of the ORDER BYclause is to follow it with the name of the column we want to sort by. This query requires that ROWID is unique (can be used as a primary key). heroes results.all() print(heroes) Code below omitted. Let's try age: SELECTsex,age,nameFROMpeopleORDERBYageLIMIT3 Where does ORDER BY fit How to remember where ORDER BYfits in the query syntax so far Well, we know that LIMITwill be the last part of virtually any statement. Because the correlated subquery is executed for every row, whether or not it's included in the result, it may not be as efficient as the window function version given below - but unlike that version it'll work on SQLite3, which doesn't support window functions. But we could as well have thousands, so lets limit the results to get only the first 3. The most basic usage of the ORDER BYclause is to follow it with the name of the column we want to sort by. The query uses a correlated subquery with a sort and limit to produce a list of ROWIDs that should appear in the final result. Here's a fairly portable query to do what you want: SELECT * This example query returns name in reverse-alphabetical order and shows only the. The ORDER BY clause goes after the FROM clause but before the LIMIT. I want the simplest solution and want to avoid temp tables. Being able to order the result rows is particularly useful when using LIMIT, as it allows us to quickly return just the 'top 3' or 'bottom 10' of the results. IN SHORT, I WANT A LIMIT WITHIN A GROUP BY. RESULTS FOR C3 - note: ROWID 6 does not appear as its score is less than 20 so only 1 record returned here C3, P7, 20, 2 RESULTS FOR C2 - note: ROWID 5 appears before ROWID 4 as ROWID 5 has lesser value RESULTS FOR C1 - note: ROWID 1 is not considered as its score < 20 C1, P2, 20, 2 If I had to run my query on above data, I would expect the following result: also where condition is score >= 20 and I want the results ordered by CID and SortKey. What query do I write so that it applies group by on CID, but instead of returning me 1 single result per group, it returns me a max of 2 results per group. table WHERE datetime (SELECT MAX(datetime) FROM table)) ORDER BY id DESC LIMIT 1. It has the following data: 1, C1, P1, 10, 1 I have a table with value as shown below id branchid qty datetime. Optional second argument for passing options:* cancel: if true, cancel query if timeout is reached.I have a table named t1 with following fields: ROWID, CID, PID, Score, SortKey Useful for complex queries that you want to make sure are not taking too long to execute. The error contains information about the query, bindings, and the timeout that was set. Sets a timeout for the query and will throw a TimeoutError if the timeout is exceeded. If you don't want to manually specify the result type, it is recommended to always use the type of last value of the chain and assign result of any future chain continuation to a separate variable (which will have a different type). ![]()
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