notes

Author: pyramation

packages/transform/AST_NOTES.md

@@ -0,0 +1,27 @@
+# AST Transformer Implementation
+
+### Transformers
+
+#### v13 → v14 (`v13-to-v14.ts`)
+- **Changes**: Field rename `relkind` → `objtype`
+- **Affected nodes**: `AlterTableStmt`, `CreateTableAsStmt`
+
+#### v14 → v15 (`v14-to-v15.ts`)
+- **Major change**: A_Const structure flattening
+  - Before: `A_Const.val.String.str`
+  - After: `A_Const.sval.sval`
+- **Field renames**:
+  - `String.str` → `String.sval`
+  - `BitString.str` → `BitString.bsval`
+  - `Float.str` → `Float.fval`
+- **Other changes**:
+  - `tables` → `pubobjects` in publication statements
+  - `tableAction` → `action` in `AlterPublicationStmt`
+
+#### v15 → v16 (`v15-to-v16.ts`)
+- **Changes**: Minimal for basic queries
+- **Advanced features**: Support for Var node changes, Aggref field rename
+
+#### v16 → v17 (`v16-to-v17.ts`)
+- **Changes**: None for basic queries
+- **Note**: Pass-through transformer for compatibility