feat: optimize expression parse #18871
Merged
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Summary
#1218 (comment)
This issue mentioned that under large_statment, the performance of databend parser is significantly lower than that of datafuison parser.
This PR attempts to discover the differences that cause poor performance and improve them
run_pratt_parser
to randomly clone the entire statement for error display, which will cause extremely high copy cost and stack overflow when large_statement is used (50% of the time)rule!
will cause repeated parse. In this PR, rule! is removed forbinary_op
,unary_op
, andjson_op
, andTokenKind
is directly judged (15% of the time onbinary_op
,unary_op
, andjson_op
)bench code on #1218 (comment)
before this PR:
after this PR:
Tips: remove src/query/ast/src/parser/parser.rs:58 I don't know why debug_assertions is still true when cargo bench
I try to minimize the branching of expr for large_statement (only #binary_op | #function_call | #column_ref | #literal)
currently, there is still a lot of backtracking under large_statment, which is also the direction that parse needs to be optimized.

Tests
Type of change
This change is