Payment terms related functions moved to separate file, common function for calculati...

[fa-stable.git] / includes / db / sql_functions.inc

diff --git a/includes/db/sql_functions.inc b/includes/db/sql_functions.inc
index 3b4b5acd499511998fd0ef9ba80c8d6a10d355d7..56392e6d9fdb7eef8c2edbd838cb7517ab2d512e 100644 (file)
--- a/includes/db/sql_functions.inc
+++ b/includes/db/sql_functions.inc
@@ -101,3 +101,33 @@ function running_total_sql($table, $column, $index)
                        (SELECT @total:=0) total_var";
 }
 
+/*
+       Return number of records in tables, where some foreign key $id is used.
+       $id - searched key value
+       $tables - array of table names (without prefix); when table name is used as a key, then
+               value is name of foreign key field. For numeric keys $stdkey field name is used.
+       $stdkey - standard name of foreign key.
+*/
+function key_in_foreign_table($id, $tables, $stdkey)
+{
+
+       if (!is_array($tables))
+               $tables = array($tables);
+
+       $sqls = array();
+       foreach ($tables as $tbl => $key) {
+               if (is_numeric($tbl)) {
+                       $tbl = $key;
+                       $key = $stdkey;
+               }
+               $sqls[] = "(SELECT COUNT(*) as cnt FROM `".TB_PREF."$tbl` WHERE `$key`=".db_escape($id).")\n";
+       }
+
+       $sql = "SELECT sum(cnt) FROM (". implode(' UNION ', $sqls).") as counts";
+
+       $result = db_query($sql, "check relations for ".implode(',',$tables)." failed");
+       $count = db_fetch($result);
+
+       return $count[0];
+}
+