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Performance Schema table_handles Table

MariaDB starting with 10.5.2

The table_handles table was added in MariaDB 10.5.2.

The table_handles table contains table lock information. It uses the wait/lock/table/sql/handler instrument, which is enabled by default.

Information includes which table handles are open, which sessions are holding the locks, and how they are locked.

The table is read-only, and TRUNCATE TABLE cannot be performed on the table.

The maximum number of opened table objects is determined by the performance_schema_max_table_handles system variable.

The table contains the following columns:

ColumnDescription
OBJECT_TYPEThe table opened by a table handle.
OBJECT_SCHEMAThe schema that contains the object.
OBJECT_NAMEThe name of the instrumented object.
OBJECT_INSTANCE_BEGINThe table handle address in memory.
OWNER_THREAD_IDThe thread owning the table handle.
OWNER_EVENT_IDThe event which caused the table handle to be opened.
INTERNAL_LOCKThe table lock used at the SQL level.
EXTERNAL_LOCKThe table lock used at the storage engine level.
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