Question

I am trying to build a search system and retrieving matching records. in this case.. i wanna let users use some especial chars for exactly build their requests. so i put these signs and then converting them to a correct SQL:
+ should be converted ro AND
/ should be converted ro OR
“ should be converted ro ( or )
for example when user entered: “book/pen”+paper
it should be converted to SQL WHERE clause:
( (myfield LIKE “%book%”) OR (myfield LIKE “%pen%”) ) AND ( myfield LIKE “%paper%”)
i implemented this with a switch case and arrays.. but i guess that there are another quick way to do that (such as regEx). have you any idea for solving it?

NOTE 1: I should collect all term from this expression and save them in another table. so, i need to collect them in an array.
NOTE 2: terms can be write in all world languages! from English to Arabic,Persian,.. may be Chinese!!!!

Thanks

Answer 1

Have a try with :

$str = '"book/pen"+paper';
// First: replace all keywords (assuming they don't contain " / + by SQL LIKE
$str = preg_replace('#([^"/+]+)#', "(myfield LIKE '%$1%')", $str);
// then replace / by OR
$str = preg_replace("#/#", " OR ", $str);
// then replace + by AND
$str = preg_replace("#\+#", " AND ", $str);
// and finaly replace pair of "" by ()
$str = preg_replace('/"([^"]+)"/', "($1)", $str);
echo $str,"\n";

output:

((myfield LIKE '%book%') OR (myfield LIKE '%pen%')) AND (myfield LIKE '%paper%')