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Documentation
/ SQL
/ Statements
Profiling Queries
DuckDB supports profiling queries via the EXPLAIN and EXPLAIN ANALYZE statements.
EXPLAIN
To see the query plan of a query without executing it, run:
EXPLAIN ⟨query⟩;
The output of EXPLAIN contains the estimated cardinalities for each operator.
EXPLAIN ANALYZE
To profile a query, run:
EXPLAIN ANALYZE ⟨query⟩;
The EXPLAIN ANALYZE statement runs the query, and shows the actual cardinalities for each operator,
as well as the cumulative wall-clock time spent in each operator.