Translate MySQL CONVERT() expressions to SQLite#356
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Promote the %simpleExpr_factored fragment to a real "simpleExprBody" rule so it creates its own AST node. This separates the core expression (CONVERT, CAST, literals, etc.) from trailing modifiers (COLLATE, CONCAT_PIPES) that remain in the parent "simpleExpr" node, making individual expression handlers simpler.
SQLite doesn't support the CONVERT() function. Translate its two forms: - CONVERT(expr, type) is equivalent to CAST(expr AS type). - CONVERT(expr USING charset) is a character set conversion that is a no-op in SQLite, as all text is stored as UTF-8. Fixes #344
JanJakes
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bgrgicak and
brandonpayton
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brandonpayton
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The Query Monitor tests failure is unrelated to this PR and I will address it separately. It seems that QM 4.0 is incompatbible with our integration. |
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Summary
Fixes #344.
MySQL's
CONVERT()function was passed through to SQLite unchanged, causing queries likeSELECT CONVERT('Customer' USING utf8mb4) COLLATE utf8mb4_binto fail with a syntax error.This PR has two parts:
Extract
simpleExprBodyas a named grammar rule. The%simpleExpr_factoredfragment is promoted to a realsimpleExprBodyrule so it creates its own AST node. This separates the core expression (CONVERT, CAST, literals, etc.) from trailing modifiers (COLLATE, CONCAT_PIPES) that remain in the parentsimpleExprnode, making individual expression handlers simpler.Translate
CONVERT()expressions. Adds explicit handling for both forms ofCONVERT()in the AST-based driver:CONVERT(expr, type)is translated toCAST(expr AS type), reusing the existingcastTypetranslation.CONVERT(expr USING charset)is reduced to just the expression, as SQLite stores all text as UTF-8 and charset conversions are not needed.Test plan
testConverttranslation test — verifies SQL-to-SQL translation for both CONVERT forms and COLLATE.testConvertExpression— verifies CONVERT with type casting (BINARY, CHAR, SIGNED, UNSIGNED, DECIMAL, DATE).testConvertUsingExpression— verifies CONVERT with charset conversion (utf8mb4, utf8, latin1).testConvertUsingWithCollate— verifies the exact query from CONVERT() queries fail with error #344.testConvertWithColumnReferences— verifies CONVERT with column references in SELECT, WHERE, and ORDER BY.