| 摘要 |
Various aspects of this disclosure are directed to receiving, by a computing device, a first table join query that may include a first group of table identifiers that identify the two or more tables. The computing device may determine whether the first table join query includes an outer join command. When the first table join query includes the outer join command, the computing device may compare the first group of table identifiers and a second group of table identifiers of one or more pre-joined tables to determine whether each of the first table identifiers matches at least one of the second group of table identifiers. The computing device may further determine whether a predicate associated with each table identifier matches a predicate associated with a matching second table identifier. When each of the predicates match, the computing device may rewrite the first table join query. |
