[tomodian]

Summary

Fixes #648.

applyLegacyCheckNormalizations turned col ~~ 'pat'::text into col LIKE 'pat' by splitting the clause on " ~~ " and cutting the right-hand side at its first ::. If anything followed the pattern, it was dropped, e.g. ) AND (b IS NOT NULL). Both sides of a diff go through the same normalisation, so plan couldn't see the loss. dump and apply to an empty schema then wrote the weaker constraint.

The fix rewrites each ~~ '<literal>'::text|varchar operand in place and leaves the rest of the expression as it is. After the rewrite, one redundant pair of outer parentheses is stripped, so a simple CHECK (col LIKE 'x') normalises exactly as before. The existing dump fixtures (e.g. bytebase) don't change.

Tests

• ir/normalize_test.go: a LIKE on its own, a LIKE followed by AND, two LIKEs, and a pattern with an escaped quote.
• testdata/diff/create_table/issue_648_check_like_keeps_trailing_conditions: the old schema has CHECK (id IS NULL OR id LIKE 'p-%') and the new one adds AND partner_id IS NOT NULL. Without the fix the plan is empty; with it the constraint is dropped and re-added.

Ran locally: go test ./ir/ ./internal/diff/ ./cmd/dump/, plus TestPlanAndApply filtered to the new case.

[greptile-apps]

Confidence Score: 4/5

[Medium impact] Fixes CHECK constraint normalization for LIKE patterns.

Fix the quoted-pattern replacement before merging; it can change the rules enforced by generated constraints.

Findings

1.  Quoted CHECK patterns change ▶

Summary

This PR rewrites LIKE expressions in place so CHECK constraints keep their trailing conditions.

• LIKE checks keep the conditions that follow their patterns.

_{Reviews (1) · Last reviewed commit: "fix: keep the conditions after LIKE in C..." · Reviewed by Greptile}

[greptile-apps]

Quoted CHECK patterns change

The global replacement changes ~~ inside quoted text, not just LIKE operators. For example, CHECK (name LIKE 'a ~~ b') arrives as name ~~ 'a ~~ b'::text and now becomes name LIKE 'a LIKE b'. The old split left this expression unchanged because it contained two occurrences. Dumps and generated constraints therefore check a different value.

Rewrite only operators outside strings and quoted identifiers, and add a regression test for this pattern.

Knowledge Base Used: Schema normalization and identity

[Copilot]

🟡 Changes recommended

The blanket replacement can modify quoted pattern contents and silently change constraint semantics.

1 open finding

• Blanket ~~ replacement corrupts quoted string literals · New

What changed in this PR

Fixes #648 by preserving conditions after LIKE patterns when normalizing PostgreSQL CHECK constraints.

Changes:

• Replaces truncating normalization with in-place rewriting.
• Adds unit tests for compound conditions and escaped quotes.
• Adds migration fixtures showing detection of a strengthened constraint.

File	Description
ir/​normalize.go	Rewrites LIKE operands without truncating trailing conditions.
ir/​normalize_test.go	Adds LIKE normalization regression tests.
testdata/​diff/​create_table/​issue_648_check_like_keeps_trailing_conditions/​old.sql	Defines the original constraint.
testdata/​diff/​create_table/​issue_648_check_like_keeps_trailing_conditions/​new.sql	Adds the required partner condition.
testdata/​diff/​create_table/​issue_648_check_like_keeps_trailing_conditions/​diff.sql	Records expected constraint replacement.
testdata/​diff/​create_table/​issue_648_check_like_keeps_trailing_conditions/​plan.json	Records structured migration steps.
testdata/​diff/​create_table/​issue_648_check_like_keeps_trailing_conditions/​plan.sql	Records executable migration SQL.
testdata/​diff/​create_table/​issue_648_check_like_keeps_trailing_conditions/​plan.txt	Records human-readable migration output.

🧠 Review effort: Balanced

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[tianzhou]

Close in favor of #649