--
-- CHAR
--
-- fixed-length by value
-- internally passed by value if <= 4 bytes in storage
SELECT char 'c' = char 'c' AS true;
 true 
------
 t
(1 row)

--
-- Build a table for testing
--
CREATE TABLE CHAR_TBL(f1 char);
INSERT INTO CHAR_TBL (f1) VALUES ('a');
INSERT INTO CHAR_TBL (f1) VALUES ('A');
-- any of the following three input formats are acceptable
INSERT INTO CHAR_TBL (f1) VALUES ('1');
INSERT INTO CHAR_TBL (f1) VALUES (2);
INSERT INTO CHAR_TBL (f1) VALUES ('3');
-- zero-length char
INSERT INTO CHAR_TBL (f1) VALUES ('');
INSERT INTO CHAR_TBL (f1) VALUES ('c     ');
SELECT c.*
   FROM CHAR_TBL c
   WHERE c.f1 = 'a';
 f1 
----
 a
(1 row)

DROP TABLE CHAR_TBL;
--
-- Now test longer arrays of char
--
CREATE TABLE CHAR_TBL(f1 char(4));
INSERT INTO CHAR_TBL (f1) VALUES ('a');
INSERT INTO CHAR_TBL (f1) VALUES ('ab');
INSERT INTO CHAR_TBL (f1) VALUES ('abcd');
INSERT INTO CHAR_TBL (f1) VALUES ('abcd    ');