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How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?

... The fastest MySQL solution, without inner queries and without GROUP BY: SELECT m.* -- get the row that contains the max value FROM topten m -- "m" from "max" LEFT JOIN topten b -- "b" from "...
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How can I get the SQL of a PreparedStatement?

... This also depends on the implementation. In MySQL -- at least the version I was using a few years ago -- the JDBC driver actually built a conventional SQL query from the template and bind variables. I guess that version of MySQL didn't support prepared statements nativ...
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Upgrading PHP in XAMPP for Windows?

... Take a backup of your htdocs and data folder (subfolder of MySQL folder), reinstall upgraded version and replace those folders. Note: In case you have changed config files like PHP (php.ini), Apache (httpd.conf) or any other, please take back up of those files as well and replace th...
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How to check if field is null or empty in MySQL?

...uld like to check in PHP , then you should do something like : $query_s =mysql_query("SELECT YOURROWNAME from `YOURTABLENAME` where name = $name"); $ertom=mysql_fetch_array($query_s); if ('' !== $ertom['YOURROWNAME']) { //do your action echo "It was filled"; } else { echo "it was empty!"; }...
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Get top n records for each group of grouped results

...g this: The version is the variables is close to being correct. However, MySQL does not guarantee the order of evaluation of expressions in the SELECT (and, in fact, sometimes evaluates them out-of-order). The key to the solution is to put all the variable assignments in a single expression; here...
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MySQL JOIN the most recent row only?

... For anyone who must work with an older version of MySQL (pre-5.0 ish) you are unable to do sub-queries for this type of query. Here is the solution I was able to do and it seemed to work great. SELECT MAX(d.id), d2.*, CONCAT(title,' ',forename,' ',surname) AS name FROM cust...
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How do I check if an index exists on a table field in MySQL?

... Use SHOW INDEX like so: SHOW INDEX FROM [tablename] Docs: https://dev.mysql.com/doc/refman/5.0/en/show-index.html share | improve this answer | follow | ...
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Is it possible to roll back CREATE TABLE and ALTER TABLE statements in major SQL databases?

...tive. Is DDL transactional according to this document? PostgreSQL - yes MySQL - no; DDL causes an implicit commit Oracle Database 11g Release 2 and above - by default, no, but an alternative called edition-based redefinition exists Older versions of Oracle - no; DDL causes an implicit commit SQL ...
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Windows: XAMPP vs WampServer vs EasyPHP vs alternative [closed]

...o, but I want to open it up further to include all possible Windows/Apache/MySQL/PHP stacks. 5 Answers ...
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MySQL CONCAT returns NULL if any field contain NULL

... mysql has IFNULL(arg, default) instead COALESCE with the same syntax – Vasilii Suricov Feb 19 '19 at 17:58 ...