Add TIDB_PARSE_TSO_LOGICAL() (#14719)

functions-and-operators/tidb-functions.md

@@ -16,6 +16,7 @@ The following functions are TiDB extensions, and are not present in MySQL:
 | [`TIDB_DECODE_PLAN(str)`](#tidb_decode_plan) | The `TIDB_DECODE_PLAN` function can be used to decode a TiDB execution plan. |
 | `TIDB_IS_DDL_OWNER()` | The `TIDB_IS_DDL_OWNER` function can be used to check whether or not the TiDB instance you are connected to is the one that is the DDL Owner. The DDL Owner is the TiDB instance that is tasked with executing DDL statements on behalf of all other nodes in the cluster. |
 | [`TIDB_PARSE_TSO(num)`](#tidb_parse_tso) | The `TIDB_PARSE_TSO` function can be used to extract the physical timestamp from a TiDB TSO timestamp. See also: [`tidb_current_ts`](/system-variables.md#tidb_current_ts). |
+| `TIDB_PARSE_TSO_LOGICAL(num)` | The `TIDB_PARSE_TSO_LOGICAL` function can be used to extract the logical timestamp from a TiDB TSO timestamp. |
 | [`TIDB_VERSION()`](#tidb_version) | The `TIDB_VERSION` function returns the TiDB version with additional build information. |
 | [`TIDB_DECODE_SQL_DIGESTS(digests, stmtTruncateLength)`](#tidb_decode_sql_digests) | The `TIDB_DECODE_SQL_DIGESTS()` function is used to query the normalized SQL statements (a form without formats and arguments) corresponding to the set of SQL digests in the cluster. |
 | `VITESS_HASH(str)` | The `VITESS_HASH` function returns the hash of a string that is compatible with Vitess' `HASH` function. This is intended to help the data migration from Vitess. |
@@ -34,6 +35,7 @@ The following functions are TiDB extensions, and are not present in MySQL:
 | [`TIDB_DECODE_PLAN(str)`](#tidb_decode_plan) | The `TIDB_DECODE_PLAN` function can be used to decode a TiDB execution plan. |
 | `TIDB_IS_DDL_OWNER()` | The `TIDB_IS_DDL_OWNER` function can be used to check whether or not the TiDB instance you are connected to is the one that is the DDL Owner. The DDL Owner is the TiDB instance that is tasked with executing DDL statements on behalf of all other nodes in the cluster. |
 | [`TIDB_PARSE_TSO(num)`](#tidb_parse_tso) | The `TIDB_PARSE_TSO` function can be used to extract the physical timestamp from a TiDB TSO timestamp. See also: [`tidb_current_ts`](/system-variables.md#tidb_current_ts). |
+| `TIDB_PARSE_TSO_LOGICAL(num)` | The `TIDB_PARSE_TSO_LOGICAL` function can be used to extract the logical timestamp from a TiDB TSO timestamp. |
 | [`TIDB_VERSION()`](#tidb_version) | The `TIDB_VERSION` function returns the TiDB version with additional build information. |
 | [`TIDB_DECODE_SQL_DIGESTS(digests, stmtTruncateLength)`](#tidb_decode_sql_digests) | The `TIDB_DECODE_SQL_DIGESTS()` function is used to query the normalized SQL statements (a form without formats and arguments) corresponding to the set of SQL digests in the cluster. |
 | `VITESS_HASH(str)` | The `VITESS_HASH` function returns the hash of a string that is compatible with Vitess' `HASH` function. This is intended to help the data migration from Vitess. |