FlyingZC opened a new issue, #27069: URL: https://github.com/apache/shardingsphere/issues/27069
# Background Hi community, This issue is for #26878. ShardingSphere parser engine helps users parse a SQL to get the AST (Abstract Syntax Tree) and visit this tree to get SQLStatement (Java Object). Currently, we are planning to enhance the support for Oracle SQL parsing in ShardingSphere. More details: https://shardingsphere.apache.org/document/current/en/reference/sharding/parse/ # Task This issue is to support more oracle sql parse, as follows: ```sql CREATE OR REPLACE TRIGGER check_user AFTER LOGON ON DATABASE BEGIN check_user; EXCEPTION WHEN OTHERS THEN RAISE_APPLICATION_ERROR (-20000, 'Unexpected error: '|| DBMS_Utility.Format_Error_Stack); END; ``` ```sql CREATE OR REPLACE TRIGGER dept_cascade3 AFTER UPDATE OF Deptno ON dept BEGIN UPDATE emp SET Update_id = NULL WHERE Update_id = Integritypackage.Updateseq; END; ``` ```sql CREATE OR REPLACE TRIGGER dept_del_cascade AFTER DELETE ON dept FOR EACH ROW -- Before row is deleted from dept, -- delete all rows from emp table whose DEPTNO is same as -- DEPTNO being deleted from dept table: BEGIN DELETE FROM emp WHERE emp.Deptno = :OLD.Deptno; END; ``` ```sql CREATE OR REPLACE TRIGGER dept_cascade2 AFTER DELETE OR UPDATE OF Deptno ON dept FOR EACH ROW -- For each department number in dept that is updated, -- cascade update to dependent foreign keys in emp table. -- Cascade update only if child row was not updated by this trigger: BEGIN IF UPDATING THEN UPDATE emp SET Deptno = :NEW.Deptno, Update_id = Integritypackage.Updateseq --from 1st WHERE emp.Deptno = :OLD.Deptno AND Update_id IS NULL; /* Only NULL if not updated by 3rd trigger fired by same triggering statement */ END IF; IF DELETING THEN -- After row is deleted from dept, -- delete all rows from emp table whose DEPTNO is same as -- DEPTNO being deleted from dept table: DELETE FROM emp WHERE emp.Deptno = :OLD.Deptno; END IF; END; ``` ```sql CREATE OR REPLACE TRIGGER dept_restrict BEFORE DELETE OR UPDATE OF Deptno ON dept FOR EACH ROW -- Before row is deleted from dept or primary key (DEPTNO) of dept is updated, -- check for dependent foreign key values in emp; -- if any are found, roll back. DECLARE Dummy INTEGER; -- Use for cursor fetch Employees_present EXCEPTION; employees_not_present EXCEPTION; -- Cursor used to check for dependent foreign key values. CURSOR Dummy_cursor (Dn NUMBER) IS SELECT Deptno FROM emp WHERE Deptno = Dn; BEGIN OPEN Dummy_cursor (:OLD.Deptno); FETCH Dummy_cursor INTO Dummy; -- If dependent foreign key is found, raise user-specified -- error code and message. If not found, close cursor -- before allowing triggering statement to complete. IF Dummy_cursor%FOUND THEN RAISE Employees_present; -- Dependent rows exist ELSE RAISE Employees_not_present; -- No dependent rows exist END IF; CLOSE Dummy_cursor; EXCEPTION WHEN Employees_present THEN CLOSE Dummy_cursor; Raise_application_error(-20001, 'Employees Present in' || ' Department ' || TO_CHAR(:OLD.DEPTNO)); WHEN Employees_not_present THEN CLOSE Dummy_cursor; END; ``` # Process 1. First confirm that this is a correct oracle sql syntax, if not please ignore; 2. Compare SQL definitions in Oficial SQL Doc and ShardingSphere SQL Doc; 3. If there is any difference in ShardingSphere SQL Doc, please correct them by referring to the Official SQL Doc; 4. Run mvn install the current_file_module; 5. Check whether there are any exceptions. If indeed, please fix them. (Especially xxxVisitor.class); 6. Add new corresponding SQL case in SQL Cases and expected parsed result in Expected Statment XML; 7. Run SQLParserParameterizedTest to make sure no exceptions. # Relevant Skills 1. Master JAVA language 2. Have a basic understanding of Antlr `g4` file 3. Be familiar with Oracle SQLs -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
