123 lines
2.1 KiB
Plaintext
123 lines
2.1 KiB
Plaintext
--
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-- CHAR
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--
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-- fixed-length by value
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-- internally passed by value if <= 4 bytes in storage
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SELECT char 'c' = char 'c' AS true;
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true
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------
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t
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(1 row)
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--
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-- Build a table for testing
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--
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CREATE TABLE CHAR_TBL(f1 char);
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INSERT INTO CHAR_TBL (f1) VALUES ('a');
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INSERT INTO CHAR_TBL (f1) VALUES ('A');
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-- any of the following three input formats are acceptable
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INSERT INTO CHAR_TBL (f1) VALUES ('1');
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INSERT INTO CHAR_TBL (f1) VALUES (2);
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INSERT INTO CHAR_TBL (f1) VALUES ('3');
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-- zero-length char
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INSERT INTO CHAR_TBL (f1) VALUES ('');
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-- try char's of greater than 1 length
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INSERT INTO CHAR_TBL (f1) VALUES ('cd');
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ERROR: value too long for type character(1)
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INSERT INTO CHAR_TBL (f1) VALUES ('c ');
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SELECT '' AS seven, * FROM CHAR_TBL;
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seven | f1
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-------+----
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| a
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| A
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| 1
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| 2
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| 3
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| c
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(7 rows)
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SELECT '' AS six, c.*
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FROM CHAR_TBL c
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WHERE c.f1 <> 'a';
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six | f1
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-----+----
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| A
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| 1
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| 2
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| 3
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| c
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(6 rows)
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SELECT '' AS one, c.*
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FROM CHAR_TBL c
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WHERE c.f1 = 'a';
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one | f1
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-----+----
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| a
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(1 row)
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SELECT '' AS five, c.*
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FROM CHAR_TBL c
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WHERE c.f1 < 'a';
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five | f1
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------+----
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| 1
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| 2
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| 3
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(4 rows)
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SELECT '' AS six, c.*
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FROM CHAR_TBL c
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WHERE c.f1 <= 'a';
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six | f1
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-----+----
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| a
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| 1
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| 2
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| 3
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(5 rows)
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SELECT '' AS one, c.*
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FROM CHAR_TBL c
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WHERE c.f1 > 'a';
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one | f1
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-----+----
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| A
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| c
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(2 rows)
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SELECT '' AS two, c.*
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FROM CHAR_TBL c
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WHERE c.f1 >= 'a';
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two | f1
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-----+----
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| a
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| A
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| c
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(3 rows)
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DROP TABLE CHAR_TBL;
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--
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-- Now test longer arrays of char
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--
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CREATE TABLE CHAR_TBL(f1 char(4));
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INSERT INTO CHAR_TBL (f1) VALUES ('a');
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INSERT INTO CHAR_TBL (f1) VALUES ('ab');
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INSERT INTO CHAR_TBL (f1) VALUES ('abcd');
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INSERT INTO CHAR_TBL (f1) VALUES ('abcde');
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ERROR: value too long for type character(4)
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INSERT INTO CHAR_TBL (f1) VALUES ('abcd ');
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SELECT '' AS four, * FROM CHAR_TBL;
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four | f1
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------+------
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| a
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| ab
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| abcd
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| abcd
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(4 rows)
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