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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.