Spanner provides a built-in SPANNER_SYS.SUPPORTED_OPTIMIZER_VERSIONS
table to keep track of query optimizer versions. You can retrieve this data
using SQL queries.
SPANNER_SYS.SUPPORTED_OPTIMIZER_VERSIONS table schema
| Column name | Type | Description | 
|---|---|---|
| VERSION | INT64 | The optimizer version. | 
| RELEASE_DATE | DATE | The release date of the optimizer version. | 
| IS_DEFAULT | BOOL | Whether the version is the default version. | 
List all supported optimizer versions
SELECT * FROM SPANNER_SYS.SUPPORTED_OPTIMIZER_VERSIONS
An example result:
| VERSION | RELEASE_DATE | IS_DEFAULT | 
|---|---|---|
| 1 | 2019-06-18 | false | 
| 2 | 2020-03-01 | false | 
| 3 | 2021-08-01 | true | 
What's next
- To learn more about the query optimizer, see Query optimizer overview.
- To learn more about how the query optimizer has evolved, see Query optimizer
versions.