The older mysql extension has the CLIENT_FOUND_ROWS
connection flag, but I couldn't find any equivalent for mysqli.
I have an update
query and want to know how many rows its where
clause matched, not how many were actually changed (as indicated by mysqli -> affected_rows
).
The only way I've figured out so far is to parse mysqli -> info
(which looks something like Rows matched: 40 Changed: 40 Warnings: 0
) with a regex. But that seems开发者_如何学C hacky.
I used the following code:
// Parse the digits from the info string that has the following format:
// Rows matched: 0 Changed: 0 Warnings: 0
preg_match_all('!\d+!', $mysqli->info, $m);
return $m[0][0];
it's in the options of mysqli_real_connect
.
Also introduced in PDO::MySQL in PHP 5.3.
You could run SELECT COUNT(*)
with the same WHERE clause before running the UPDATE. That will give you a count of the number of rows that would be matched.
Also SELECT ROW_COUNT()
can give the number of rows affected by update query.
From the official docs, looks like this can be achieved by building the PDO
object like this:
new PDO($dsn, $u, $p, array(PDO::MYSQL_ATTR_FOUND_ROWS => true));
I did an explode function on the results returned from the info command and then took index[1].
$affected = explode(":", $connection->info);
$rowsAffected = $affected[1];
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