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1. Sqlite order by and limit top and bottom driver#
2. Sqlite order by and limit top and bottom portable#
3. Sqlite order by and limit top and bottom code#

So the code would be $data = $pdo -> query ( "SELECT * FROM users" )-> fetchAll () īut most of time we have to use a variable or two in the query, and in such a case we should use a prepared statement (also called a parameterized query), first preparing a query with parameters (or placeholder marks) and then executing it, sending variables separately. It will put all the rows returned by a query into a PHP array, that later can be used to output the data using a template (which is considered much better than echoing the data right during the fetch process). For example, if such processing is the only action that needs to be taken, or if the data needs to be pre-processed somehow before use.īut the most preferred way to fetch multiple rows which would to be shown on a web-page is calling the great helper method called fetchAll(). This method could be recommended if rows have to be processed one by one. The most traditional way is to use the fetch() method within a while loop: $stmt = $pdo -> query ( "SELECT * FROM users" ) There are two ways to fetch multiple rows returned by a query. Note that in PHP you can "chain" method calls, calling a method of the returned object already, like: $user = $pdo -> query ( "SELECT * FROM users ORDER BY id DESC LIMIT 1" )-> fetch () Selecting multiple rows $stmt = $pdo -> query ( "SELECT * FROM users ORDER BY id DESC LIMIT 1" ) If a query is supposed to return just a single row, then you can just call fetch() method of the $stmt variable: // getting the last registered user This will give us an $stmt object that can be used to fetch the actual rows. $stmt = $pdo -> query ( "SELECT * FROM users" ) If there are no variables going to be used in the query, we can use a conventional query() method instead of prepare and execute. Just make sure you've got a properly configured PDO connection variable that needs in order to run SQL queries with PDO and to inform you of the possible errors. I will show examples for the every case so you can choose one that suits you best. There are several ways to run a SELECT query using PDO, that differ mainly by the presence of parameters, type of parameters, and the result type.

Sqlite order by and limit top and bottom driver#

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. I tested the above in PostgreSQL 9.2 and in SQLite3 3.7.11 it works fine in both. This query requires that ROWID is unique (can be used as a primary key). 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. The query uses a correlated subquery with a sort and limit to produce a list of ROWIDs that should appear in the final result.

Sqlite order by and limit top and bottom portable#

Here's a fairly portable query to do what you want: SELECT * I want the simplest solution and want to avoid temp tables. 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. It has the following data: 1, C1, P1, 10, 1 I have a table named t1 with following fields: ROWID, CID, PID, Score, SortKey