• TRACE
    • 语法图
    • 示例
    • MySQL 兼容性
    • 另请参阅

    TRACE

    TRACE 语句用于提供查询执行的详细信息，可通过 TiDB 服务器状态端口所公开的图形界面进行查看。

    语法图

    TraceStmt:

    TraceStmt

    TraceableStmt:

    TraceableStmt

    示例

    1. mysql> trace format='row' select * from mysql.user;
    2. +---------------------------+-----------------+------------+
    3. | operation                 | startTS         | duration   |
    4. +---------------------------+-----------------+------------+
    5. | session.getTxnFuture      | 10:33:34.647148 | 3.847µs    |
    6. |   ├─session.Execute       | 10:33:34.647146 | 536.233µs  |
    7. |   ├─session.ParseSQL      | 10:33:34.647182 | 19.868µs   |
    8. |   ├─executor.Compile      | 10:33:34.647219 | 295.688µs  |
    9. |   ├─session.runStmt       | 10:33:34.647533 | 116.229µs  |
    10. |   ├─session.CommitTxn     | 10:33:34.647631 | 5.44µs     |
    11. |   ├─recordSet.Next        | 10:33:34.647707 | 833.103µs  |
    12. |   ├─tableReader.Next      | 10:33:34.647709 | 806.783µs  |
    13. |   ├─recordSet.Next        | 10:33:34.648572 | 19.367µs   |
    14. |   └─tableReader.Next      | 10:33:34.648575 | 1.783µs    |
    15. +---------------------------+-----------------+------------+
    16. 10 rows in set (0.00 sec)
    18. mysql> CREATE TABLE t1 (id int not null primary key auto_increment);
    19. Query OK, 0 rows affected (0.11 sec)
    21. mysql> INSERT INTO t1 VALUES (1),(2),(3),(4),(5);
    22. Query OK, 5 rows affected (0.02 sec)
    23. Records: 5  Duplicates: 0  Warnings: 0
    25. mysql> TRACE FORMAT='json' SELECT * FROM t1 WHERE id = 2\G
    26. operation: [
    27.     {"ID":{"Trace":"60d20d005593de87","Span":"44e5b309242ffe2f","Parent":"79d146dac9a29a7e"},
    28.         "Annotations":[
    29.             {"Key":"Name","Value":"c2Vzc2lvbi5nZXRUeG5GdXR1cmU="},
    30.             {"Key":"_schema:name","Value":null},
    31.             {"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE2MTQ3ODYtMDY6MDA="},
    32.             {"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE2MjA0MDYtMDY6MDA="},
    33.             {"Key":"_schema:Timespan","Value":null}
    34.         ],
    35.         "Sub":[
    36.             {"ID":{"Trace":"60d20d005593de87","Span":"4dbf8f2ca373b4b0","Parent":"79d146dac9a29a7e"},
    37.             "Annotations":[
    38.                 {"Key":"Name","Value":"c2Vzc2lvbi5QYXJzZVNRTA=="},
    39.                 {"Key":"_schema:name","Value":null},
    40.                 {"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE2NjE1MTQtMDY6MDA="},
    41.                 {"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3MDYxNjgtMDY6MDA="},
    42.                 {"Key":"_schema:Timespan","Value":null}
    43.             ],
    44.             "Sub":null},
    45.             {"ID":{"Trace":"60d20d005593de87","Span":"6b6d6916df809604","Parent":"79d146dac9a29a7e"},
    46.             "Annotations":[
    47.                 {"Key":"Name","Value":"ZXhlY3V0b3IuQ29tcGlsZQ=="},
    48.                 {"Key":"_schema:name","Value":null},
    49.                 {"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3NTcyODUtMDY6MDA="},
    50.                 {"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3MzE0MjYtMDY6MDA="},
    51.                 {"Key":"_schema:Timespan","Value":null}
    52.             ],
    53.             "Sub":null},
    54.             {"ID":{"Trace":"60d20d005593de87","Span":"3f1bcdd402a72911","Parent":"79d146dac9a29a7e"},
    55.             "Annotations":[
    56.                 {"Key":"Name","Value":"c2Vzc2lvbi5Db21taXRUeG4="},
    57.                 {"Key":"_schema:name","Value":null},
    58.                 {"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3OTgyNjItMDY6MDA="},
    59.                 {"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE4MDU1NzYtMDY6MDA="},
    60.                 {"Key":"_schema:Timespan","Value":null}
    61.             ],
    62.             "Sub":null},
    63.             {"ID":{"Trace":"60d20d005593de87","Span":"58c1f7d66dc5afbc","Parent":"79d146dac9a29a7e"},
    64.             "Annotations":[
    65.                 {"Key":"Name","Value":"c2Vzc2lvbi5ydW5TdG10"},
    66.                 {"Key":"_schema:name","Value":null},
    67.                 {"Key":"Msg","Value":"eyJzcWwiOiJTRUxFQ1QgKiBGUk9NIHQxIFdIRVJFIGlkID0gMiJ9"},
    68.                 {"Key":"Time","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3ODA1NjgtMDY6MDA="},
    69.                 {"Key":"_schema:log","Value":null},
    70.                 {"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE4MTk5MzMtMDY6MDA="},
    71.                 {"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3NzcyNDItMDY6MDA="},
    72.                 {"Key":"_schema:Timespan","Value":null}
    73.             ],
    74.             "Sub":null},
    75.             {"ID":{"Trace":"60d20d005593de87","Span":"6bd8cc440fb31ed7","Parent":"79d146dac9a29a7e"},
    76.             "Annotations":[
    77.                 {"Key":"Name","Value":"c2Vzc2lvbi5FeGVjdXRl"},
    78.                 {"Key":"_schema:name","Value":null},
    79.                 {"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE2MTEwODktMDY6MDA="},
    80.                 {"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE4NTU0My0wNjowMA=="},
    81.                 {"Key":"_schema:Timespan","Value":null}
    82.             ],
    83.             "Sub":null},
    84.             {"ID":{"Trace":"60d20d005593de87","Span":"61d0b809f6cc018b","Parent":"79d146dac9a29a7e"},
    85.             "Annotations":[
    86.                 {"Key":"Name","Value":"cmVjb3JkU2V0Lk5leHQ="},
    87.                 {"Key":"_schema:name","Value":null},
    88.                 {"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE4NzQ1NTYtMDY6MDA="},
    89.                 {"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDIyOTg4NjYtMDY6MDA="},
    90.                 {"Key":"_schema:Timespan","Value":null}
    91.             ],
    92.             "Sub":null},
    93.             {"ID":{"Trace":"60d20d005593de87","Span":"2bd2c3d47ccb1133","Parent":"79d146dac9a29a7e"},
    94.             "Annotations":[
    95.                 {"Key":"Name","Value":"cmVjb3JkU2V0Lk5leHQ="},
    96.                 {"Key":"_schema:name","Value":null},
    97.                 {"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDIzMjY0ODgtMDY6MDA="},
    98.                 {"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDIzMjkwMDMtMDY6MDA="},
    99.                 {"Key":"_schema:Timespan","Value":null}
    100.             ],
    101.             "Sub":null}
    102.         ]
    103.     }
    104. ]
    105. 1 row in set (0.00 sec)

    可将 JSON 格式的跟踪文件粘贴到跟踪查看器中。查看器可通过 TiDB 状态端口访问：

    TiDB Trace Viewer-1

    TiDB Trace Viewer-2

    MySQL 兼容性

    TRACE 语句是 TiDB 对 MySQL 语法的扩展。

    另请参阅

    • EXPLAIN ANALYZE