Oracle

Configuration

• ORA-12516: TNS:listener could not find available handler with matching protocol stack
  • Edit %oracle_home%/database/init<SID>.ora
  • Add

PROCESSES=200

FAQ

How do I realize an auto-incrementing field?

CREATE TABLE    MYTABLE (
                ID          NUMBER(11, 0)   NOT NULL 
           -- , FIELD       
                );

CREATE SEQUENCE MYTABLE_ID_SEQ
    START WITH 1 
    INCREMENT BY 1 
    NOMAXVALUE; 

CREATE TRIGGER MYTABLE_ID_TRG
    BEFORE INSERT ON MYTABLE
    FOR EACH ROW
    BEGIN
        SELECT MYTABLE_ID_SEQ.NEXTVAL 
          INTO :NEW.ID 
          FROM DUAL;
    END;

How do I rollback?

SAVEPOINT MYSAVEPOINT;
-- ...
ROLLBACK TO MYSAVEPOINT;