Optimize SQL — sql_optimize • polyglotSQL

Applies the upstream optimizer rule set (predicate pushdown, join reordering, CTE and subquery elimination, expression simplification, etc.) and returns the rewritten SQL.

Usage

sql_optimize(sql, dialect = "generic", schema = NULL)

Arguments

sql: A single character string with one or more SQL statements (separated by ;).
dialect: Dialect used for parsing.
schema: Optional schema specification (see as_polyglot_schema()); improves resolution of unqualified or ambiguous columns.

Value

A character vector with one optimized statement per input statement.

Examples

sql_optimize("SELECT * FROM (SELECT a FROM t) AS sub WHERE sub.a > 1")
#> [1] "WITH _cte AS (SELECT a FROM t) SELECT * FROM _cte AS sub WHERE sub.a > 1"