--
-- Check constraints
-- Constraints can be specified with either DEFAULT or CHECK clauses.
--

--
-- DEFAULT syntax
--

CREATE TABLE DEFAULT_TBL (i int DEFAULT 100,
 x text DEFAULT 'vadim', f float8 DEFAULT 123.456);

INSERT INTO DEFAULT_TBL VALUES (1, 'thomas', 57.0613);
INSERT INTO DEFAULT_TBL VALUES (1, 'bruce');
INSERT INTO DEFAULT_TBL (i, f) VALUES (2, 987.654);
INSERT INTO DEFAULT_TBL (x) VALUES ('tgl');
INSERT INTO DEFAULT_TBL VALUES (3, null, 1.0);

SELECT '' AS four, * FROM DEFAULT_TBL;

CREATE SEQUENCE DEFAULT_SEQ;
CREATE TABLE DEFAULTEXPR_TBL (i1 int DEFAULT 100 + (200-199) * 2,
 i2 int DEFAULT nextval('default_seq'));

INSERT INTO DEFAULTEXPR_TBL VALUES (-1, -2);
INSERT INTO DEFAULTEXPR_TBL (i1) VALUES (-3);
INSERT INTO DEFAULTEXPR_TBL (i2) VALUES (-4);
INSERT INTO DEFAULTEXPR_TBL (i2) VALUES (NULL);
SELECT '' AS four, * FROM DEFAULTEXPR_TBL;

-- errors
-- test for:
--  extraneous comma
--  booleans not allowed
CREATE TABLE error_tbl (i int DEFAULT (100, ));
CREATE TABLE error_tbl (b1 bool DEFAULT 1 < 2);

--
-- CHECK syntax
--

CREATE TABLE CHECK_TBL (x int) 
 CONSTRAINT CHECK_CON CHECK (x > 3);

INSERT INTO CHECK_TBL VALUES (5);
INSERT INTO CHECK_TBL VALUES (4);
INSERT INTO CHECK_TBL VALUES (3);
INSERT INTO CHECK_TBL VALUES (2);
INSERT INTO CHECK_TBL VALUES (6);
INSERT INTO CHECK_TBL VALUES (1);

CREATE SEQUENCE CHECK_SEQ;
CREATE TABLE CHECK2_TBL (x int, y text, z int) 
 CONSTRAINT SEQUENCE_CON CHECK (x > 3 and y <> 'check failed' and x < 8);
INSERT INTO CHECK2_TBL VALUES (4, 'check ok', -2);
INSERT INTO CHECK2_TBL VALUES (1, 'x check failed', -2);
INSERT INTO CHECK2_TBL VALUES (5, 'z check failed', 10);
INSERT INTO CHECK2_TBL VALUES (0, 'check failed', -2);
INSERT INTO CHECK2_TBL VALUES (6, 'check failed', 11);
INSERT INTO CHECK2_TBL VALUES (7, 'check ok', 7);

--
-- Check constraints on INSERT
--

CREATE SEQUENCE INSERT_SEQ;

CREATE TABLE INSERT_TBL (x INT DEFAULT nextval('insert_seq'),
y TEXT DEFAULT '-NULL-', z INT DEFAULT -1 * currval('insert_seq') ) 
CONSTRAINT INSERT_CON CHECK (x >= 3 AND y <> 'check failed' AND x < 8), 
CHECK x + z = 0;

INSERT INTO INSERT_TBL VALUES (null, null, null);
INSERT INTO INSERT_TBL(x,z) VALUES (2, -2);

SELECT * FROM INSERT_TBL;
SELECT nextval('insert_seq');

INSERT INTO INSERT_TBL(y) VALUES ('Y');
INSERT INTO INSERT_TBL(y) VALUES ('Y');
INSERT INTO INSERT_TBL(x,z) VALUES (1, -2);
INSERT INTO INSERT_TBL(z,x) VALUES (-7,  7);
INSERT INTO INSERT_TBL VALUES (5, 'check failed', -5);
INSERT INTO INSERT_TBL VALUES (7, '!check failed', -7);
INSERT INTO INSERT_TBL(y) VALUES ('-!NULL-');
SELECT * FROM INSERT_TBL;
INSERT INTO INSERT_TBL(y,z) VALUES ('check failed', 4);
INSERT INTO INSERT_TBL(x,y) VALUES (5, 'check failed');
INSERT INTO INSERT_TBL(x,y) VALUES (5, '!check failed');
INSERT INTO INSERT_TBL(y) VALUES ('-!NULL-');
SELECT * FROM INSERT_TBL;
SELECT nextval('insert_seq');
INSERT INTO INSERT_TBL(y) VALUES ('Y');
SELECT currval('insert_seq');

--
-- Check constraints on INSERT INTO
--

DELETE FROM INSERT_TBL;
DROP SEQUENCE INSERT_SEQ;
CREATE SEQUENCE INSERT_SEQ START 4;
CREATE TABLE TEMP (xd INT, yd TEXT, zd INT);

INSERT INTO TEMP VALUES (null, 'Y', null);
INSERT INTO TEMP VALUES (5, '!check failed', null);
INSERT INTO TEMP VALUES (null, 'try again', null);
INSERT INTO INSERT_TBL(y) select yd from TEMP;
SELECT * FROM INSERT_TBL;
INSERT INTO INSERT_TBL SELECT * FROM TEMP WHERE yd = 'try again';
INSERT INTO INSERT_TBL(y,z) SELECT yd, -7 FROM TEMP WHERE yd = 'try again';
INSERT INTO INSERT_TBL(y,z) SELECT yd, -8 FROM TEMP WHERE yd = 'try again';
SELECT * FROM INSERT_TBL;

DROP TABLE TEMP;

--
-- Check constraints on UPDATE
--

UPDATE INSERT_TBL SET x = NULL WHERE x = 6;
UPDATE INSERT_TBL SET x = 6 WHERE x = 6;
UPDATE INSERT_TBL SET x = -z, z = -x;
UPDATE INSERT_TBL SET x = z, z = x;
SELECT * FROM INSERT_TBL;

--
-- Check constraints on COPY FROM
--

CREATE TABLE COPY_TBL (x INT, y TEXT, z INT) 
 CONSTRAINT COPY_CON CHECK (x > 3 AND y <> 'check failed' AND x < 7 );

COPY COPY_TBL FROM '_OBJWD_/data/constro.data';
SELECT * FROM COPY_TBL;
COPY COPY_TBL FROM '_OBJWD_/data/constrf.data';

SELECT * FROM COPY_TBL;