Task Brief

Date: 2026-04-14
GitHub Issue: #65
Status: AWAITING IMPLEMENTATION

Description

Implement "Rename Table" support in the FluentSQL DDL API. This allows developers to generate ALTER TABLE ... RENAME TO (or equivalent) SQL strings in a database-agnostic way using the Schema entry point.

Context

The "Rename Table" feature (ESP-047 / ESP-031) is a documented but unimplemented DDL capability. Adding this feature aligns the code with the user guides and completes a key vertical in the DDL infrastructure, supporting Firebird, PostgreSQL, MySQL, MSSQL, and SQLite.

Scope

• Define IFluentDDLAlterTableRenameTableDef and IFluentDDLAlterTableRenameTableBuilder in FluentSQL.Interfaces.pas.
• Add AlterTableRename(const AOldName, ANewName: string): IFluentDDLAlterTableRenameTableBuilder to IFluentSchema and TFluentSchema.
• Implement TFluentDDLAlterTableRenameTableBuilder in FluentSQL.DDL.pas.
• Add AlterTableRenameTable method to IFluentDDLSerialize and TFluentDDLSerializeAbstract.
• Implement dialect-specific overrides in:
  • FluentSQL.DDL.Serialize.Firebird.pas
  • FluentSQL.DDL.Serialize.PostgreSQL.pas
  • FluentSQL.DDL.Serialize.MySQL.pas
  • FluentSQL.DDL.Serialize.MSSQL.pas (using sp_rename)
  • FluentSQL.DDL.Serialize.SQLite.pas
• Add unit tests in test.ddl.pas for all dialects and validation cases.

Out of scope

• Renaming multiple tables in one call.
• Support for dialects beyond the core 5 (PG, FB, MySQL, MSSQL, SQLite).
• Execution of the generated SQL.

Acceptance criteria

• Schema(dbnPostgreSQL).AlterTableRename('A', 'B').AsString returns 'ALTER TABLE "A" RENAME TO "B"'.
• Schema(dbnFirebird).AlterTableRename('A', 'B').AsString returns 'ALTER TABLE "A" TO "B"'.
• Schema(dbnMySQL).AlterTableRename('A', 'B').AsString returns 'ALTER TABLE ARENAME TOB'.
• Schema(dbnMSSQL).AlterTableRename('A', 'B').AsString returns EXEC sp_rename 'A', 'B'.
• Schema(dbnSQLite).AlterTableRename('A', 'B').AsString returns 'ALTER TABLE "A" RENAME TO "B"'.
• Identifiers are correctly quoted according to dialect rules.
• Raises EArgumentException if names are empty or identical after Trim.
• 100% of new tests in TTestDDLAlterTableRenameTable fixture PASS.

Likely impacted files

• Source/Core/FluentSQL.Interfaces.pas
• Source/Core/FluentSQL.DDL.pas
• Source/Core/FluentSQL.DDL.SerializeAbstract.pas
• Source/Drivers/FluentSQL.DDL.Serialize.Firebird.pas
• Source/Drivers/FluentSQL.DDL.Serialize.PostgreSQL.pas
• Source/Drivers/FluentSQL.DDL.Serialize.MySQL.pas
• Source/Drivers/FluentSQL.DDL.Serialize.MSSQL.pas
• Source/Drivers/FluentSQL.DDL.Serialize.SQLite.pas
• Test Delphi/test.ddl.pas