CREATE TABLE INFO_TABLE (

INFO_F1 VARCHAR2(10),

INFO_F2 VARCHAR2(20),

INFO_F3 VARCHAR2(20),

COMM_CODE VARCHAR2(10)

)

CREATE TABLE CODE_TABLE (

GROUP_CODE VARCHAR2(10),

COMM_CODE VARCHAR2(10),

COMM_NAME VARCHAR2(20)

)

INFO_TABLE PRIMARY KEY(INFO_F1)

CODE_TABLE PRIMARY KEY(GROUP_CODE, COMM_CODE)

-- 1번

SELECT

A.INFO_F1,

A.INFO_F2,

A.INFO_F3,

B.COMM_CODE,

B.COMM_NAME

FROM INFO_TABLE A

LEFT JOIN (SELECT * FROM CODE_TABLE WHERE GROUP_CODE = 'TEST') B ON (A.COMM_CODE = B.COMM_CODE)

-- 2번

SELECT

A.INFO_F1,

A.INFO_F2,

A.INFO_F3,

B.COMM_CODE,

B.COMM_NAME

FROM INFO_TABLE A

LEFT JOIN CODE_TABLE ON (A.COMM_CODE = B.COMM_CODE AND B.GROUP_CODE = 'TEST')

-- 3번

SELECT

A.INFO_F1,

A.INFO_F2,

A.INFO_F3,

B.COMM_CODE,

B.COMM_NAME

FROM INFO_TABLE A

LEFT JOIN CODE_TABLE ON (A.COMM_CODE = B.COMM_CODE)

WHERE B.GROUP_CODE = 'TEST'

위의 1, 2, 3 쿼리중 어느 쿼리가 가장 좋은 쿼리 인가요?