/**
* Get a single value from a table.
*
* @param string $sql an SQL statement expected to return a single value.
* @return mixed the specified value, or false if an error occured.
*/
function get_field_sql($sql)
{
global $CFG;
/// Strip potential LIMIT uses arriving here, debugging them (MDL-7173)
$newsql = preg_replace('/ LIMIT [0-9, ]+$/is', '', $sql);
if ($newsql != $sql) {
debugging('Incorrect use of LIMIT clause (not cross-db) in call to get_field_sql(): ' . s($sql), DEBUG_DEVELOPER);
$sql = $newsql;
}
$rs = get_recordset_sql($sql, 0, 1);
if ($rs && $rs->RecordCount() == 1) {
/// DIRTY HACK to retrieve all the ' ' (1 space) fields converted back
/// to '' (empty string) for Oracle. It's the only way to work with
/// all those NOT NULL DEFAULT '' fields until we definetively delete them
if ($CFG->dbfamily == 'oracle') {
$value = reset($rs->fields);
onespace2empty($value);
return $value;
}
/// End of DIRTY HACK
return reset($rs->fields);
} else {
return false;
}
}
/**
* Get a single value from a table (allowing for the use of LIMIT clauses).
*
* @param string $sql an SQL statement expected to return a single value
* (with a limit clause calculated depending on the database type).
* @param int $limitfrom return a subset of records, starting at this point (optional).
*
* @return mixed the specified value, or false if an error occured.
*/
function get_field_sql($sql, $limitfrom = 0)
{
global $CFG;
//use the optional starting point
$rs = get_recordset_sql($sql, $limitfrom, 1);
if ($rs && $rs->RecordCount() == 1) {
/// DIRTY HACK to retrieve all the ' ' (1 space) fields converted back
/// to '' (empty string) for Oracle. It's the only way to work with
/// all those NOT NULL DEFAULT '' fields until we definetively delete them
if ($CFG->dbfamily == 'oracle') {
$value = reset($rs->fields);
onespace2empty($value);
return $value;
}
/// End of DIRTY HACK
return reset($rs->fields);
} else {
return false;
}
}
