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4 changes: 3 additions & 1 deletion sql-statements/sql-statement-create-index.md
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Expand Up @@ -366,7 +366,9 @@ See [Index Selection - Use multi-valued indexes](/choose-index.md#use-multi-valu
- If a table uses multi-valued indexes, you cannot back up, replicate, or import the table using BR, TiCDC, or TiDB Lightning to a TiDB cluster earlier than v6.6.0.
- For a query with complex conditions, TiDB might not be able to select multi-valued indexes. For information on the condition patterns supported by multi-valued indexes, refer to [Use multi-valued indexes](/choose-index.md#use-multi-valued-indexes).

## Partial indexes <span class="version-mark">New in v8.5.7</span>
## Partial indexes

<span class="version-mark">New in v8.5.7 for TiDB Self-Managed and TiDB Cloud Dedicated, and in CLOUD.202603.1 for TiDB Cloud Essential and Premium</span>

A partial index is an index built on a subset of rows in a table. When creating a partial index, you can specify a conditional expression, also known as a predicate, to define that subset of rows. The index contains entries only for the rows that satisfy the predicate.

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2 changes: 1 addition & 1 deletion sql-statements/sql-statement-modify-column.md
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Expand Up @@ -15,7 +15,7 @@ The following are some common examples of column type changes that require Reorg
- Modifying the `DECIMAL` precision
- Reducing the length of `VARCHAR(10)` to `VARCHAR(5)`

Starting from v8.5.5, TiDB optimizes some column type changes that previously required Reorg-Data. When the following conditions are met, TiDB rebuilds only the affected indexes instead of the entire table, thereby improving execution efficiency:
Starting from v8.5.5 for TiDB Self-Managed and TiDB Cloud Dedicated, and from CLOUD.202603.1 for TiDB Cloud Essential and Premium, TiDB optimizes some column type changes that previously required Reorg-Data. When the following conditions are met, TiDB rebuilds only the affected indexes instead of the entire table, thereby improving execution efficiency:

- The current session uses a strict [SQL mode](/sql-mode.md) (`sql_mode` includes `STRICT_TRANS_TABLES` or `STRICT_ALL_TABLES`).
- The table has no TiFlash replicas.
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2 changes: 1 addition & 1 deletion sql-statements/sql-statement-select.md
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Expand Up @@ -106,7 +106,7 @@ TableSample ::=

> **Note:**
>
> - Starting from v8.5.6, TiDB supports using table aliases in the `FOR UPDATE OF` clause. To maintain backward compatibility, you can still reference the base table name when an alias is defined, but this triggers a warning that recommends using the explicit alias. When a query involves multiple tables with the same name across different databases (for example, `FROM db1.t, db2.t FOR UPDATE OF t`), TiDB now matches the target table from left to right based on the order in the `FROM` clause, rather than the current database context. To avoid ambiguity, it is recommended that you specify the database name or use aliases in the `FOR UPDATE OF` clause.
> - Starting from v8.5.6 for TiDB Self-Managed and TiDB Cloud Dedicated, and from CLOUD.202603.1 for TiDB Cloud Essential and Premium, TiDB supports using table aliases in the `FOR UPDATE OF` clause. To maintain backward compatibility, you can still reference the base table name when an alias is defined, but this triggers a warning that recommends using the explicit alias. When a query involves multiple tables with the same name across different databases (for example, `FROM db1.t, db2.t FOR UPDATE OF t`), TiDB now matches the target table from left to right based on the order in the `FROM` clause, rather than the current database context. To avoid ambiguity, it is recommended that you specify the database name or use aliases in the `FOR UPDATE OF` clause.
> - Starting from v6.6.0, TiDB supports [Resource Control](/tidb-resource-control-ru-groups.md). You can use this feature to execute SQL statements with different priorities in different resource groups. By configuring proper quotas and priorities for these resource groups, you can gain better scheduling control for SQL statements with different priorities. When resource control is enabled, statement priority (`HIGH_PRIORITY`) will no longer take effect. It is recommended that you use [Resource Control](/tidb-resource-control-ru-groups.md) to manage resource usage for different SQL statements.

## Examples
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