multiple queries and mysql_query function

sgalmeida

Greetings,

I have a problem 🙁 I want to execute several queries (several updates) at one time, but I don't know how to do it. My SQL statement is:

$sqlStatement=" UPDATE minhatabela SET campo01='' WHERE campo01='".$parametro."';";
$sqlStatement="UPDATE minhatabela SET campo02='' WHERE campo02='".$parametro."';";
$sqlStatement="UPDATE minhatabela SET campo03='' WHERE campo03='".$parametro."';";
$sqlStatement="UPDATE minhatabela SET campo04='' WHERE campo04='".$parametro."';";
$sqlStatement="UPDATE minhatabela SET campo05='' WHERE campo05='".$parametro."';";
$result=mysql_query($sqlStatement);

but this is not executed.

If I do the following

$sqlStatement=" UPDATE minhatabela SET campo01='' WHERE campo01='".$parametro."';";
$result=mysql_query($sqlStatement);
$sqlStatement.="UPDATE minhatabela SET campo02='' WHERE campo02='".$parametro."';";
$result=mysql_query($sqlStatement);
$sqlStatement.="UPDATE minhatabela SET campo03='' WHERE campo03='".$parametro."';";
$result=mysql_query($sqlStatement);
$sqlStatement.="UPDATE minhatabela SET campo04='' WHERE campo04='".$parametro."';";
$result=mysql_query($sqlStatement);
$sqlStatement.="UPDATE minhatabela SET campo05='' WHERE campo05='".$parametro."';";
$result=mysql_query($sqlStatement);

the updates are executed, but as you can see, I have to do one query at a time.

Is there a solution to make several sql statements using one mysql_query? Any ideas?

Thank you very much.

Sérgio

nnichols

When making multiple queries like this you have to do them separately when using the bundled MySQL library. This carries very little overhead, so there's no need to worry about it. The main overhead is in establishing the db connection in the first instance. Once it is there the execution of multiple queries should be very quick, only a few msecs less than being able to run them with a single call.

There's no bonus in jumping in and out of the string when assigning your SQL to the vars using double quotes.

$sqlStatement = "UPDATE minhatabela SET campo01='' WHERE campo01='$parametro'";
$result=mysql_query($sqlStatement); 
....

Hope this helps 😉