Exemple #1
0
        public static TriggerSchema GenerateUpdateTrigger(ForeignKeySchema fks)
        {
            TriggerSchema trigger = new TriggerSchema();

            trigger.Name  = MakeTriggerName(fks, "fku");
            trigger.Type  = TriggerType.Before;
            trigger.Event = TriggerEvent.Update;
            trigger.Table = fks.TableName;

            string triggerName = trigger.Name;
            string nullString  = "";

            if (fks.IsNullable)
            {
                nullString = " NEW." + fks.ColumnName + " IS NOT NULL AND";
            }

            trigger.Body = "SELECT RAISE(ROLLBACK, 'update on table " + fks.TableName +
                           " violates foreign key constraint " + triggerName + "')" +
                           " WHERE" + nullString + " (SELECT " + fks.ForeignColumnName +
                           " FROM " + fks.ForeignTableName + " WHERE " + fks.ForeignColumnName + " = NEW." +
                           fks.ColumnName +
                           ") IS NULL; ";

            return(trigger);
        }
Exemple #2
0
        public static TriggerSchema GenerateDeleteTrigger(ForeignKeySchema fks)
        {
            TriggerSchema trigger = new TriggerSchema();

            trigger.Name  = MakeTriggerName(fks, "fkd");
            trigger.Type  = TriggerType.Before;
            trigger.Event = TriggerEvent.Delete;
            trigger.Table = fks.ForeignTableName;

            string triggerName = trigger.Name;

            if (!fks.CascadeOnDelete)
            {
                trigger.Body = "SELECT RAISE(ROLLBACK, 'delete on table " + fks.ForeignTableName +
                               " violates foreign key constraint " + triggerName + "')" +
                               " WHERE (SELECT " + fks.ColumnName +
                               " FROM " + fks.TableName + " WHERE " + fks.ColumnName + " = OLD." +
                               fks.ForeignColumnName +
                               ") IS NOT NULL; ";
            }
            else
            {
                trigger.Body = "DELETE FROM [" + fks.TableName + "] WHERE " + fks.ColumnName + " = OLD." +
                               fks.ForeignColumnName + "; ";
            }
            return(trigger);
        }
Exemple #3
0
 private static string MakeTriggerName(ForeignKeySchema fks, string prefix)
 {
     return(prefix + "_" + fks.TableName + "_" + fks.ColumnName + "_" + fks.ForeignTableName + "_" + fks.ForeignColumnName);
 }