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:
TraceableStmt:
示例
trace format='row' select * from mysql.user;
+---------------------------+-----------------+------------+
| operation | startTS | duration |
+---------------------------+-----------------+------------+
| session.getTxnFuture | 10:33:34.647148 | 3.847µs |
| ├─session.Execute | 10:33:34.647146 | 536.233µs |
| ├─session.ParseSQL | 10:33:34.647182 | 19.868µs |
| ├─executor.Compile | 10:33:34.647219 | 295.688µs |
| ├─session.runStmt | 10:33:34.647533 | 116.229µs |
| ├─session.CommitTxn | 10:33:34.647631 | 5.44µs |
| ├─recordSet.Next | 10:33:34.647707 | 833.103µs |
| ├─tableReader.Next | 10:33:34.647709 | 806.783µs |
| ├─recordSet.Next | 10:33:34.648572 | 19.367µs |
| └─tableReader.Next | 10:33:34.648575 | 1.783µs |
+---------------------------+-----------------+------------+
10 rows in set (0.00 sec)
CREATE TABLE t1 (id int not null primary key AUTO_INCREMENT);
Query OK, 0 rows affected (0.11 sec)
INSERT INTO t1 VALUES (1),(2),(3),(4),(5);
Query OK, 5 rows affected (0.02 sec)
Records: 5 Duplicates: 0 Warnings: 0
TRACE FORMAT='json' SELECT * FROM t1 WHERE id = 2;
operation: [
{"ID":{"Trace":"60d20d005593de87","Span":"44e5b309242ffe2f","Parent":"79d146dac9a29a7e"},
"Annotations":[
{"Key":"Name","Value":"c2Vzc2lvbi5nZXRUeG5GdXR1cmU="},
{"Key":"_schema:name","Value":null},
{"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE2MTQ3ODYtMDY6MDA="},
{"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE2MjA0MDYtMDY6MDA="},
{"Key":"_schema:Timespan","Value":null}
],
"Sub":[
{"ID":{"Trace":"60d20d005593de87","Span":"4dbf8f2ca373b4b0","Parent":"79d146dac9a29a7e"},
"Annotations":[
{"Key":"Name","Value":"c2Vzc2lvbi5QYXJzZVNRTA=="},
{"Key":"_schema:name","Value":null},
{"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE2NjE1MTQtMDY6MDA="},
{"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3MDYxNjgtMDY6MDA="},
{"Key":"_schema:Timespan","Value":null}
],
"Sub":null},
{"ID":{"Trace":"60d20d005593de87","Span":"6b6d6916df809604","Parent":"79d146dac9a29a7e"},
"Annotations":[
{"Key":"Name","Value":"ZXhlY3V0b3IuQ29tcGlsZQ=="},
{"Key":"_schema:name","Value":null},
{"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3NTcyODUtMDY6MDA="},
{"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3MzE0MjYtMDY6MDA="},
{"Key":"_schema:Timespan","Value":null}
],
"Sub":null},
{"ID":{"Trace":"60d20d005593de87","Span":"3f1bcdd402a72911","Parent":"79d146dac9a29a7e"},
"Annotations":[
{"Key":"Name","Value":"c2Vzc2lvbi5Db21taXRUeG4="},
{"Key":"_schema:name","Value":null},
{"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3OTgyNjItMDY6MDA="},
{"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE4MDU1NzYtMDY6MDA="},
{"Key":"_schema:Timespan","Value":null}
],
"Sub":null},
{"ID":{"Trace":"60d20d005593de87","Span":"58c1f7d66dc5afbc","Parent":"79d146dac9a29a7e"},
"Annotations":[
{"Key":"Name","Value":"c2Vzc2lvbi5ydW5TdG10"},
{"Key":"_schema:name","Value":null},
{"Key":"Msg","Value":"eyJzcWwiOiJTRUxFQ1QgKiBGUk9NIHQxIFdIRVJFIGlkID0gMiJ9"},
{"Key":"Time","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3ODA1NjgtMDY6MDA="},
{"Key":"_schema:log","Value":null},
{"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE4MTk5MzMtMDY6MDA="},
{"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE3NzcyNDItMDY6MDA="},
{"Key":"_schema:Timespan","Value":null}
],
"Sub":null},
{"ID":{"Trace":"60d20d005593de87","Span":"6bd8cc440fb31ed7","Parent":"79d146dac9a29a7e"},
"Annotations":[
{"Key":"Name","Value":"c2Vzc2lvbi5FeGVjdXRl"},
{"Key":"_schema:name","Value":null},
{"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE2MTEwODktMDY6MDA="},
{"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE4NTU0My0wNjowMA=="},
{"Key":"_schema:Timespan","Value":null}
],
"Sub":null},
{"ID":{"Trace":"60d20d005593de87","Span":"61d0b809f6cc018b","Parent":"79d146dac9a29a7e"},
"Annotations":[
{"Key":"Name","Value":"cmVjb3JkU2V0Lk5leHQ="},
{"Key":"_schema:name","Value":null},
{"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDE4NzQ1NTYtMDY6MDA="},
{"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDIyOTg4NjYtMDY6MDA="},
{"Key":"_schema:Timespan","Value":null}
],
"Sub":null},
{"ID":{"Trace":"60d20d005593de87","Span":"2bd2c3d47ccb1133","Parent":"79d146dac9a29a7e"},
"Annotations":[
{"Key":"Name","Value":"cmVjb3JkU2V0Lk5leHQ="},
{"Key":"_schema:name","Value":null},
{"Key":"Span.Start","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDIzMjY0ODgtMDY6MDA="},
{"Key":"Span.End","Value":"MjAxOS0wNC0xN1QxMDozOToxMC45NDIzMjkwMDMtMDY6MDA="},
{"Key":"_schema:Timespan","Value":null}
],
"Sub":null}
]
}
]
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：
MySQL 兼容性
TRACE 语句是 TiDB 对 MySQL 语法的扩展。