[2/2] spark git commit: [SPARK-16621][SQL] Generate stable SQLs in SQLBuilder

[SPARK-16621][SQL] Generate stable SQLs in SQLBuilder Currently, the generated SQLs have not-stable IDs for generated attributes. The stable generated SQL will give more benefit for understanding or testing the queries. This PR provides stable SQL generation by the followings. - Provide unique

[2/2] spark git commit: [SPARK-16621][SQL] Generate stable SQLs in SQLBuilder

[SPARK-16621][SQL] Generate stable SQLs in SQLBuilder ## What changes were proposed in this pull request? Currently, the generated SQLs have not-stable IDs for generated attributes. The stable generated SQL will give more benefit for understanding or testing the queries. This PR provides stable