sqlglot_transpile_parse_transform_optimize_sql_quickstart.py

1import sqlglot
2
3# Transpile SQL from one dialect to another
4sql = "SELECT TOP 10 * FROM table"
5transpiled = sqlglot.transpile(sql, read="tsql", write="spark")[0]
6print(transpiled)
7# SELECT * FROM table LIMIT 10
8
9# Parse SQL into an expression tree
10expression = sqlglot.parse_one("SELECT a, b + 1 AS c FROM table")
11
12# Access specific nodes in the expression tree
13print(expression.find(sqlglot.exp.Column))
14# a
15
16# Transform the expression tree
17transformed = expression.transform(lambda node: sqlglot.exp.Star() if isinstance(node, sqlglot.exp.Column) else node)
18print(transformed.sql())
19# SELECT *, * + 1 AS c FROM table
20
21# Optimize SQL
22from sqlglot.optimizer import optimize
23optimized = optimize(sqlglot.parse_one("SELECT * FROM x JOIN y ON x.a = y.a WHERE x.a = 1"))
24print(optimized.sql())
25# SELECT * FROM x JOIN y ON y.a = 1 WHERE x.a = 1