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EXPLAIN AST

Returns the abstract syntax tree (AST) of an SQL statement. The command breaks an SQL statement into syntactic parts and represents them in a hierarchical structure.

Syntax

EXPLAIN AST <statement>

Examples

EXPLAIN AST create user 'test'@'localhost' identified with sha256_password by 'new_password';

----
CreateUser (children 3)
├── User 'test'@'localhost'
├── AuthType sha256_password
└── Password "new_password"
EXPLAIN AST insert into t1 (a, b) values (1, 2),(3, 4);

----
Insert (children 3)
├── TableIdentifier t1
├── Columns (children 2)
│ ├── Identifier a
│ └── Identifier b
└── Source (children 1)
└── ValueSource
EXPLAIN AST select * from t1 inner join t2 on t1.a = t2.a and t1.b = t2.b and t1.a > 2;

----
Query (children 1)
└── QueryBody (children 1)
└── SelectQuery (children 2)
├── SelectList (children 1)
│ └── Target *
└── TableList (children 1)
└── TableJoin (children 1)
└── Join (children 3)
├── TableIdentifier t1
├── TableIdentifier t2
└── ConditionOn (children 1)
└── Function AND (children 2)
├── Function AND (children 2)
│ ├── Function = (children 2)
│ │ ├── ColumnIdentifier t1.a
│ │ └── ColumnIdentifier t2.a
│ └── Function = (children 2)
│ ├── ColumnIdentifier t1.b
│ └── ColumnIdentifier t2.b
└── Function > (children 2)
├── ColumnIdentifier t1.a
└── Literal Integer(2)
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