Leaderboard

don't bother with the mysqli extension. it is overly complicated, inconsistent, and in the case of procedural vs OOP statements, has different error responses for the same root problem. instead, use the much simpler, consistent, and more modern PDO extension. in php8+, both the mysqli and PDO extensions use exceptions for errors by default. the line of code that @Barand posted enables exceptions for errors for the msyqli extension. when you use exceptions for database statement errors, php will 'automatically' display or log the raw database errors, via an uncaught exception error. therefore, you can remove any existing error handling logic, since it won't ever get executed upon an error, simplifying the code. you should also name the connection variable as to the type of connection it contains, $mysqli/$pdo. this will let anyone looking at the code know what extension it is using, and also let you search for which code has been converted and which hasn't. you also need to use a prepared query when supplying external, unknown, dynamic values to a query when it gets executed, so that any sql special characters in a value cannot break the sql query syntax, which is how sql injection is accomplished. if you switch to the much simpler PDO extension, after you prepared the query, you can simply supply an array of the input values to the ->execute([...]) call.

The ORDER BY at the end of a set of UNIONs applies to the whole resultset. You may need a two-query approach (no data so untested) -- QUERY 1 CREATE TABLE copylinks SELECT * FROM `links` as l LEFT JOIN `accounts` as a ON a.id=l.author WHERE `l`.`live` = '1' ORDER BY `l`.`lastVisitDateTime` DESC LIMIT 10; -- QUERY 2 INSERT INTO copylinks SELECT * FROM `links` as l LEFT JOIN `accounts` as a ON a.id=l.author LEFT JOIN copylinks l2 ON l.id = l2.id WHERE `l`.`live` = '1' AND `l`.`linklocation` = 'main' AND l2.id IS NULL ORDER BY `l`.`timestamp` DESC; -- CHECK RESULT SELECT * FROM copylinks;