mySQL：如何将搜索值与变量结合起来？

Question

I'm sure that there is a stupidly simple solution to this, but unfortunately my google-fu is too weak to find it.

I have a number of different tables for sizing, all following the same naming convention i.e size_001, size_002 etc. Within a loop I need to get the size entry that matches with the results already found.

Unfortunately there are no totally unique identifiers, as they repeat in each table (roman numerals for sizing). But they are unique in each individual table. So what I've tried so far looks a little bit like this:

SELECT * FROM CONCAT('size_00', '.$sizeTableID[$j].') WHERE sizeName LIKE '$sizeNames[$j]'"

Where $sizeTableId is a number from 1-9 and sizeName is a string e.g II or VI or, occasionally (because there's no consisitency), 2 etc

I've also tried ''$var'' inside the CONCAT and not using the CONCAT at all. Really I just need a way to join the database.size_00 and an integer variable.

Answer 1

If I understand correctly, this is actually simple:

$tablename = 'size00'.$sizeTableID[$j];
$sql = "SELECT * FROM $tablename WHERE sizeName LIKE '{$sizeNames[$j]}'";

and I think that solves it.