{"version":3,"file":"indexes.mjs","names":[],"sources":["../../src/sql/indexes.ts"],"sourcesContent":["import type { FullSchemaIndex } from \"../schema.js\";\n\ntype IndexTypeHint = { indexType: string };\ntype IndexDropHint = { isPrimary: boolean; isUnique: boolean };\n\nexport function isIndexSupported(index: IndexTypeHint) {\n return index.indexType === \"btree\" || index.indexType === \"gin\";\n}\n\n/**\n * Doesn't necessarily decide whether the index can be dropped but can be\n * used to not even try dropping indexes that _definitely_ cannot be dropped\n */\nexport function isIndexProbablyDroppable(index: IndexDropHint) {\n /* TODO: until we have a better solution, this is the best we have */\n /* The is_unique check is problematic only if the column is declared as unique */\n return !index.isPrimary && !index.isUnique;\n}\n\nexport type DuplicateIndexGroup =\n | { kind: \"exact\"; indexes: FullSchemaIndex[] }\n | {\n kind: \"prefix\";\n indexes: FullSchemaIndex[];\n sharedPrefix: FullSchemaIndex[\"keyColumns\"];\n };\n\nfunction columnsEqual(\n a: FullSchemaIndex[\"keyColumns\"],\n b: FullSchemaIndex[\"keyColumns\"],\n): boolean {\n if (a.length !== b.length) return false;\n for (let i = 0; i < a.length; i++) {\n if (\n a[i].name.toString() !== b[i].name.toString() ||\n (a[i].order ?? null) !== (b[i].order ?? null) ||\n (a[i].opclass ?? null) !== (b[i].opclass ?? null)\n ) {\n return false;\n }\n }\n return true;\n}\n\nfunction indexesAreEqual(a: FullSchemaIndex, b: FullSchemaIndex): boolean {\n return (\n a.schemaName.toString() === b.schemaName.toString() &&\n a.tableName.toString() === b.tableName.toString() &&\n a.indexType === b.indexType &&\n (a.wherePredicate ?? null) === (b.wherePredicate ?? null) &&\n columnsEqual(a.keyColumns, b.keyColumns)\n );\n}\n\nfunction sharedPrefixColumns(\n shorter: FullSchemaIndex,\n longer: FullSchemaIndex,\n): FullSchemaIndex[\"keyColumns\"] | null {\n if (\n shorter.schemaName.toString() !== longer.schemaName.toString() ||\n shorter.tableName.toString() !== longer.tableName.toString() ||\n shorter.indexType !== longer.indexType ||\n shorter.indexType !== \"btree\" ||\n shorter.wherePredicate !== undefined ||\n longer.wherePredicate !== undefined ||\n shorter.keyColumns.length >= longer.keyColumns.length\n ) {\n return null;\n }\n for (let i = 0; i < shorter.keyColumns.length; i++) {\n const s = shorter.keyColumns[i];\n const l = longer.keyColumns[i];\n if (\n s.name.toString() !== l.name.toString() ||\n (s.order ?? null) !== (l.order ?? null) ||\n (s.opclass ?? null) !== (l.opclass ?? null)\n ) {\n return null;\n }\n }\n return shorter.keyColumns;\n}\n\nexport function groupDuplicateIndexes(\n indexes: FullSchemaIndex[],\n): DuplicateIndexGroup[] {\n const groups: DuplicateIndexGroup[] = [];\n\n for (const index of indexes) {\n const existing = groups.find(\n (g) => g.kind === \"exact\" && indexesAreEqual(g.indexes[0], index),\n );\n if (existing) {\n existing.indexes.push(index);\n } else {\n groups.push({ kind: \"exact\", indexes: [index] });\n }\n }\n\n const exactGroups = groups.filter((g) => g.indexes.length > 1);\n\n const representatives = groups\n .filter((g) => g.indexes.length === 1)\n .map((g) => g.indexes[0]);\n\n const prefixGroups: Extract[] = [];\n\n for (const shorter of representatives) {\n const existing = prefixGroups.find((g) =>\n g.indexes.some(\n (idx) =>\n sharedPrefixColumns(shorter, idx) !== null ||\n sharedPrefixColumns(idx, shorter) !== null,\n ),\n );\n if (existing) {\n if (!existing.indexes.includes(shorter)) {\n existing.indexes.push(shorter);\n }\n } else {\n const longer = representatives.find(\n (idx) => idx !== shorter && sharedPrefixColumns(shorter, idx) !== null,\n );\n if (longer) {\n const sharedPrefix = sharedPrefixColumns(shorter, longer)!;\n prefixGroups.push({\n kind: \"prefix\",\n indexes: [longer, shorter],\n sharedPrefix,\n });\n }\n }\n }\n\n return [...exactGroups, ...prefixGroups];\n}\n"],"mappings":";;AAKA,SAAgB,iBAAiB,OAAsB;AACrD,QAAO,MAAM,cAAc,WAAW,MAAM,cAAc;;;;;;AAO5D,SAAgB,yBAAyB,OAAsB;AAG7D,QAAO,CAAC,MAAM,aAAa,CAAC,MAAM;;AAWpC,SAAS,aACP,GACA,GACS;AACT,KAAI,EAAE,WAAW,EAAE,OAAQ,QAAO;AAClC,MAAK,IAAI,IAAI,GAAG,IAAI,EAAE,QAAQ,IAC5B,KACE,EAAE,GAAG,KAAK,UAAU,KAAK,EAAE,GAAG,KAAK,UAAU,KAC5C,EAAE,GAAG,SAAS,WAAW,EAAE,GAAG,SAAS,UACvC,EAAE,GAAG,WAAW,WAAW,EAAE,GAAG,WAAW,MAE5C,QAAO;AAGX,QAAO;;AAGT,SAAS,gBAAgB,GAAoB,GAA6B;AACxE,QACE,EAAE,WAAW,UAAU,KAAK,EAAE,WAAW,UAAU,IACnD,EAAE,UAAU,UAAU,KAAK,EAAE,UAAU,UAAU,IACjD,EAAE,cAAc,EAAE,cACjB,EAAE,kBAAkB,WAAW,EAAE,kBAAkB,SACpD,aAAa,EAAE,YAAY,EAAE,WAAW;;AAI5C,SAAS,oBACP,SACA,QACsC;AACtC,KACE,QAAQ,WAAW,UAAU,KAAK,OAAO,WAAW,UAAU,IAC9D,QAAQ,UAAU,UAAU,KAAK,OAAO,UAAU,UAAU,IAC5D,QAAQ,cAAc,OAAO,aAC7B,QAAQ,cAAc,WACtB,QAAQ,mBAAmB,KAAA,KAC3B,OAAO,mBAAmB,KAAA,KAC1B,QAAQ,WAAW,UAAU,OAAO,WAAW,OAE/C,QAAO;AAET,MAAK,IAAI,IAAI,GAAG,IAAI,QAAQ,WAAW,QAAQ,KAAK;EAClD,MAAM,IAAI,QAAQ,WAAW;EAC7B,MAAM,IAAI,OAAO,WAAW;AAC5B,MACE,EAAE,KAAK,UAAU,KAAK,EAAE,KAAK,UAAU,KACtC,EAAE,SAAS,WAAW,EAAE,SAAS,UACjC,EAAE,WAAW,WAAW,EAAE,WAAW,MAEtC,QAAO;;AAGX,QAAO,QAAQ;;AAGjB,SAAgB,sBACd,SACuB;CACvB,MAAM,SAAgC,EAAE;AAExC,MAAK,MAAM,SAAS,SAAS;EAC3B,MAAM,WAAW,OAAO,MACrB,MAAM,EAAE,SAAS,WAAW,gBAAgB,EAAE,QAAQ,IAAI,MAAM,CAClE;AACD,MAAI,SACF,UAAS,QAAQ,KAAK,MAAM;MAE5B,QAAO,KAAK;GAAE,MAAM;GAAS,SAAS,CAAC,MAAM;GAAE,CAAC;;CAIpD,MAAM,cAAc,OAAO,QAAQ,MAAM,EAAE,QAAQ,SAAS,EAAE;CAE9D,MAAM,kBAAkB,OACrB,QAAQ,MAAM,EAAE,QAAQ,WAAW,EAAE,CACrC,KAAK,MAAM,EAAE,QAAQ,GAAG;CAE3B,MAAM,eAAmE,EAAE;AAE3E,MAAK,MAAM,WAAW,iBAAiB;EACrC,MAAM,WAAW,aAAa,MAAM,MAClC,EAAE,QAAQ,MACP,QACC,oBAAoB,SAAS,IAAI,KAAK,QACtC,oBAAoB,KAAK,QAAQ,KAAK,KACzC,CACF;AACD,MAAI;OACE,CAAC,SAAS,QAAQ,SAAS,QAAQ,CACrC,UAAS,QAAQ,KAAK,QAAQ;SAE3B;GACL,MAAM,SAAS,gBAAgB,MAC5B,QAAQ,QAAQ,WAAW,oBAAoB,SAAS,IAAI,KAAK,KACnE;AACD,OAAI,QAAQ;IACV,MAAM,eAAe,oBAAoB,SAAS,OAAO;AACzD,iBAAa,KAAK;KAChB,MAAM;KACN,SAAS,CAAC,QAAQ,QAAQ;KAC1B;KACD,CAAC;;;;AAKR,QAAO,CAAC,GAAG,aAAa,GAAG,aAAa"}