preg_replace

[rklockner]

I'm trying to search a string for all occurences of a pattern, then append text after that pattern.  The example is:

 

SUM("foo") as "bar"

 

and have it display as:

 

SUM("foo") over() as "bar"

 

The "SUM" could be any SQL aggregate and be case insensitive.  So For bonus points, let's say the valid aggregates are  array('SUM', 'MAX', 'MIN', 'AVG').  My plan right now is to figure it out for SUM, then loop it replacing the aggregate.

 

This is what I have so far... and it is not working.

 

$l= 'SUM("foo") as "bar"';

$l=preg_replace('/([^"]+")/','\0 over()',$l);

 

Thanks,

 

Ryan

[rklockner]

I should also note that "foo" may, or may not, have quotes around it.

[Psycho]

Are "foo" and "bar" always going to be "foo" and "bar" or can they be variable text values?

 

EDIT: Also, you say the value inside the aggregate function may or may not have quotes. Can it use single quotes as well? And what about the quotes around "Bar" can that use single or double quotes - or no quotes?

Edited July 11, 2014 by Psycho

[Psycho]

I made some assumptions and made this so it would be very flexible

$functions = array('SUM', 'MAX', 'MIN', 'AVG');
$patterns = array();
$replacemetns = array();
foreach($functions as $func)
{
    $patterns[] = "#({$func})\(([^\)]*)\) as (\"){0,1}([^\"]*)(\"){0,1}#";
    $replacements[] = "\\1(\\2) over() \\3\\4\\5";
}
 
$output = preg_replace($patterns, $replacements, $input);

If this is your input

SELECT field1, field2, field3,
       SUM('field3') as 'field3sum',      --Single quotes
       MAX("field4") as "field4max",      --Double quote
       AVG(field5) as field5avg           --No quotes
FROM table_name

This will be the output

SELECT field1, field2, field3,
       SUM('field3') over() 'field3sum',  --Single quotes
       MAX("field4") over() "field4max",  --Double quote
       AVG(field5) over() field5avg       --No quotes
FROM table_name

Edited July 11, 2014 by Psycho