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SQL select only rows with max value on a column [duplicate]
...ce...
All you need is a GROUP BY clause with the MAX aggregate function:
SELECT id, MAX(rev)
FROM YourTable
GROUP BY id
It's never that simple, is it?
I just noticed you need the content column as well.
This is a very common question in SQL: find the whole data for the row with some max value ...
ng-options with simple array init
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You actually had it correct in your third attempt.
<select ng-model="myselect" ng-options="o as o for o in options"></select>
See a working example here:
http://plnkr.co/edit/xEERH2zDQ5mPXt9qCl6k?p=preview
The trick is that AngularJS writes the keys as numbers from...
-didSelectRowAtIndexPath: not being called
...de a tab view. In my UITableViewController , I implemented -tableView:didSelectRowAtIndexPath: , but when I select a row at runtime, the method isn't being called. The table view is being populated though, so I know that other tableView methods in my controller are being called.
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How do you use script variables in psql?
...t myvariable value
... and can then be substituted, for example, as ...
SELECT * FROM :myvariable.table1;
... or ...
SELECT * FROM table1 WHERE :myvariable IS NULL;
edit: As of psql 9.1, variables can be expanded in quotes as in:
\set myvariable value
SELECT * FROM table1 WHERE column1 ...
How do you create a random string that's suitable for a session ID in PostgreSQL?
...sion verification using PostgreSQL. I know I can get a random number with SELECT random() , so I tried SELECT md5(random()) , but that doesn't work. How can I do this?
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MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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How can prepared statements protect from SQL injection attacks?
...ample shows it (all examples in PHP/Mysql):
$expected_data = 1;
$query = "SELECT * FROM users where id=$expected_data";
will produce a regular query
SELECT * FROM users where id=1
while this code
$spoiled_data = "1; DROP TABLE users;"
$query = "SELECT * FROM users where id=$spoiled_da...
Row count with PDO
...
$sql = "SELECT count(*) FROM `table` WHERE foo = ?";
$result = $con->prepare($sql);
$result->execute([$bar]);
$number_of_rows = $result->fetchColumn();
Not the most elegant way to do it, plus it involves an extra query...
How do I UPDATE from a SELECT in SQL Server?
... SQL Server , it is possible to insert rows into a table with an INSERT.. SELECT statement:
35 Answers
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✔ Checkmark selected row in UITableViewCell
...pment newbie. I want to add a checkmark to my UITableViewCell when it is selected. The checkmark should be removed when another row is selected. How would I do this?
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