Expression Audits#

This section records per-version audit notes for Spark expressions that have been audited for Comet compatibility. These are findings from auditing the Spark implementation across versions (3.4.3, 3.5.8, 4.0.1), not a statement of support status.

Two kinds of audit are recorded per expression:

  • Correctness audits compare the Spark implementation across versions and note divergences and test-coverage gaps. Use the audit-comet-expression skill, which appends its findings to the relevant category page below.

  • Performance audits record when a native expression has been performance-tuned, so contributors can see at a glance which expressions have already been optimized. Recorded as a dated Performance (tuned ...) line under the expression, they name the technique, the measured speedup, the linking PR, and the benchmark file. Use the optimize-comet-expression skill (see Optimizing Scalar Expressions), which appends this line after a change is benchmarked and merged.

For the authoritative list of which expressions Comet supports, see the user guide Spark Expression Support.