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