-- -- BIT types -- -- -- Build tables for testing -- CREATE TABLE BIT_TABLE(b BIT(11)); INSERT INTO BIT_TABLE VALUES (B'10'); -- too short ERROR: bit string length 2 does not match type bit(11) INSERT INTO BIT_TABLE VALUES (B'00000000000'); INSERT INTO BIT_TABLE VALUES (B'11011000000'); INSERT INTO BIT_TABLE VALUES (B'01010101010'); INSERT INTO BIT_TABLE VALUES (B'101011111010'); -- too long ERROR: bit string length 12 does not match type bit(11) --INSERT INTO BIT_TABLE VALUES ('X554'); --INSERT INTO BIT_TABLE VALUES ('X555'); SELECT * FROM BIT_TABLE; b ------------- 00000000000 11011000000 01010101010 (3 rows) CREATE TABLE VARBIT_TABLE(v BIT VARYING(11)); INSERT INTO VARBIT_TABLE VALUES (B''); INSERT INTO VARBIT_TABLE VALUES (B'0'); INSERT INTO VARBIT_TABLE VALUES (B'010101'); INSERT INTO VARBIT_TABLE VALUES (B'01010101010'); INSERT INTO VARBIT_TABLE VALUES (B'101011111010'); -- too long ERROR: bit string too long for type bit varying(11) --INSERT INTO VARBIT_TABLE VALUES ('X554'); --INSERT INTO VARBIT_TABLE VALUES ('X555'); SELECT * FROM VARBIT_TABLE; v ------------- 0 010101 01010101010 (4 rows) -- Concatenation SELECT v, b, (v || b) AS concat FROM BIT_TABLE, VARBIT_TABLE ORDER BY 3; v | b | concat -------------+-------------+------------------------ | 00000000000 | 00000000000 0 | 00000000000 | 000000000000 0 | 01010101010 | 001010101010 010101 | 00000000000 | 01010100000000000 | 01010101010 | 01010101010 01010101010 | 00000000000 | 0101010101000000000000 01010101010 | 01010101010 | 0101010101001010101010 010101 | 01010101010 | 01010101010101010 01010101010 | 11011000000 | 0101010101011011000000 010101 | 11011000000 | 01010111011000000 0 | 11011000000 | 011011000000 | 11011000000 | 11011000000 (12 rows) -- Length SELECT b, length(b) AS lb FROM BIT_TABLE; b | lb -------------+---- 00000000000 | 11 11011000000 | 11 01010101010 | 11 (3 rows) SELECT v, length(v) AS lv FROM VARBIT_TABLE; v | lv -------------+---- | 0 0 | 1 010101 | 6 01010101010 | 11 (4 rows) -- Substring SELECT b, SUBSTRING(b FROM 2 FOR 4) AS sub_2_4, SUBSTRING(b FROM 7 FOR 13) AS sub_7_13, SUBSTRING(b FROM 6) AS sub_6 FROM BIT_TABLE; b | sub_2_4 | sub_7_13 | sub_6 -------------+---------+----------+-------- 00000000000 | 0000 | 00000 | 000000 11011000000 | 1011 | 00000 | 000000 01010101010 | 1010 | 01010 | 101010 (3 rows) SELECT v, SUBSTRING(v FROM 2 FOR 4) AS sub_2_4, SUBSTRING(v FROM 7 FOR 13) AS sub_7_13, SUBSTRING(v FROM 6) AS sub_6 FROM VARBIT_TABLE; v | sub_2_4 | sub_7_13 | sub_6 -------------+---------+----------+-------- | | | 0 | | | 010101 | 1010 | | 1 01010101010 | 1010 | 01010 | 101010 (4 rows) --- Bit operations DROP TABLE varbit_table; CREATE TABLE varbit_table (a BIT VARYING(16), b BIT VARYING(16)); COPY varbit_table FROM stdin; SELECT a, b, ~a AS "~ a", a & b AS "a & b", a | b AS "a | b", a # b AS "a # b" FROM varbit_table; a | b | ~ a | a & b | a | b | a # b ------------------+------------------+------------------+------------------+------------------+------------------ 00001111 | 00010000 | 11110000 | 00000000 | 00011111 | 00011111 00011111 | 00010001 | 11100000 | 00010001 | 00011111 | 00001110 00101111 | 00010010 | 11010000 | 00000010 | 00111111 | 00111101 00111111 | 00010011 | 11000000 | 00010011 | 00111111 | 00101100 10001111 | 00000100 | 01110000 | 00000100 | 10001111 | 10001011 0000000000001111 | 0000000000010000 | 1111111111110000 | 0000000000000000 | 0000000000011111 | 0000000000011111 0000000100100011 | 1111111111111111 | 1111111011011100 | 0000000100100011 | 1111111111111111 | 1111111011011100 0010010001101000 | 0010010001101000 | 1101101110010111 | 0010010001101000 | 0010010001101000 | 0000000000000000 1111101001010000 | 0000010110101111 | 0000010110101111 | 0000000000000000 | 1111111111111111 | 1111111111111111 0001001000110100 | 1111111111110101 | 1110110111001011 | 0001001000110100 | 1111111111110101 | 1110110111000001 (10 rows) SELECT a,b,a=b AS "a>=b",a>b AS "a>b",a<>b AS "a<>b" FROM varbit_table; a | b | a=b | a>b | a<>b ------------------+------------------+-----+------+-----+------+-----+------ 00001111 | 00010000 | t | t | f | f | f | t 00011111 | 00010001 | f | f | f | t | t | t 00101111 | 00010010 | f | f | f | t | t | t 00111111 | 00010011 | f | f | f | t | t | t 10001111 | 00000100 | f | f | f | t | t | t 0000000000001111 | 0000000000010000 | t | t | f | f | f | t 0000000100100011 | 1111111111111111 | t | t | f | f | f | t 0010010001101000 | 0010010001101000 | f | t | t | t | f | f 1111101001010000 | 0000010110101111 | f | f | f | t | t | t 0001001000110100 | 1111111111110101 | t | t | f | f | f | t (10 rows) SELECT a,a<<4 AS "a<<4",b,b>>2 AS "b>>2" FROM varbit_table; a | a<<4 | b | b>>2 ------------------+------------------+------------------+------------------ 00001111 | 11110000 | 00010000 | 00000100 00011111 | 11110000 | 00010001 | 00000100 00101111 | 11110000 | 00010010 | 00000100 00111111 | 11110000 | 00010011 | 00000100 10001111 | 11110000 | 00000100 | 00000001 0000000000001111 | 0000000011110000 | 0000000000010000 | 0000000000000100 0000000100100011 | 0001001000110000 | 1111111111111111 | 0011111111111111 0010010001101000 | 0100011010000000 | 0010010001101000 | 0000100100011010 1111101001010000 | 1010010100000000 | 0000010110101111 | 0000000101101011 0001001000110100 | 0010001101000000 | 1111111111110101 | 0011111111111101 (10 rows) DROP TABLE varbit_table; --- Bit operations DROP TABLE bit_table; CREATE TABLE bit_table (a BIT(16), b BIT(16)); COPY bit_table FROM stdin; SELECT a,b,~a AS "~ a",a & b AS "a & b", a|b AS "a | b", a # b AS "a # b" FROM bit_table; a | b | ~ a | a & b | a | b | a # b ------------------+------------------+------------------+------------------+------------------+------------------ 0000111100000000 | 0001000000000000 | 1111000011111111 | 0000000000000000 | 0001111100000000 | 0001111100000000 0001111100000000 | 0001000100000000 | 1110000011111111 | 0001000100000000 | 0001111100000000 | 0000111000000000 0010111100000000 | 0001001000000000 | 1101000011111111 | 0000001000000000 | 0011111100000000 | 0011110100000000 0011111100000000 | 0001001100000000 | 1100000011111111 | 0001001100000000 | 0011111100000000 | 0010110000000000 1000111100000000 | 0000010000000000 | 0111000011111111 | 0000010000000000 | 1000111100000000 | 1000101100000000 0000000000001111 | 0000000000010000 | 1111111111110000 | 0000000000000000 | 0000000000011111 | 0000000000011111 0000000100100011 | 1111111111111111 | 1111111011011100 | 0000000100100011 | 1111111111111111 | 1111111011011100 0010010001101000 | 0010010001101000 | 1101101110010111 | 0010010001101000 | 0010010001101000 | 0000000000000000 1111101001010000 | 0000010110101111 | 0000010110101111 | 0000000000000000 | 1111111111111111 | 1111111111111111 0001001000110100 | 1111111111110101 | 1110110111001011 | 0001001000110100 | 1111111111110101 | 1110110111000001 (10 rows) SELECT a,b,a=b AS "a>=b",a>b AS "a>b",a<>b AS "a<>b" FROM bit_table; a | b | a=b | a>b | a<>b ------------------+------------------+-----+------+-----+------+-----+------ 0000111100000000 | 0001000000000000 | t | t | f | f | f | t 0001111100000000 | 0001000100000000 | f | f | f | t | t | t 0010111100000000 | 0001001000000000 | f | f | f | t | t | t 0011111100000000 | 0001001100000000 | f | f | f | t | t | t 1000111100000000 | 0000010000000000 | f | f | f | t | t | t 0000000000001111 | 0000000000010000 | t | t | f | f | f | t 0000000100100011 | 1111111111111111 | t | t | f | f | f | t 0010010001101000 | 0010010001101000 | f | t | t | t | f | f 1111101001010000 | 0000010110101111 | f | f | f | t | t | t 0001001000110100 | 1111111111110101 | t | t | f | f | f | t (10 rows) SELECT a,a<<4 AS "a<<4",b,b>>2 AS "b>>2" FROM bit_table; a | a<<4 | b | b>>2 ------------------+------------------+------------------+------------------ 0000111100000000 | 1111000000000000 | 0001000000000000 | 0000010000000000 0001111100000000 | 1111000000000000 | 0001000100000000 | 0000010001000000 0010111100000000 | 1111000000000000 | 0001001000000000 | 0000010010000000 0011111100000000 | 1111000000000000 | 0001001100000000 | 0000010011000000 1000111100000000 | 1111000000000000 | 0000010000000000 | 0000000100000000 0000000000001111 | 0000000011110000 | 0000000000010000 | 0000000000000100 0000000100100011 | 0001001000110000 | 1111111111111111 | 0011111111111111 0010010001101000 | 0100011010000000 | 0010010001101000 | 0000100100011010 1111101001010000 | 1010010100000000 | 0000010110101111 | 0000000101101011 0001001000110100 | 0010001101000000 | 1111111111110101 | 0011111111111101 (10 rows) DROP TABLE bit_table; -- The following should fail select B'001' & B'10'; ERROR: cannot AND bit strings of different sizes select B'0111' | B'011'; ERROR: cannot OR bit strings of different sizes select B'0010' # B'011101'; ERROR: cannot XOR bit strings of different sizes -- More position tests, checking all the boundary cases SELECT POSITION(B'1010' IN B'0000101'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'1010' IN B'00001010'); -- 5 position ---------- 5 (1 row) SELECT POSITION(B'1010' IN B'00000101'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'1010' IN B'000001010'); -- 6 position ---------- 6 (1 row) SELECT POSITION(B'' IN B'00001010'); -- 1 position ---------- 1 (1 row) SELECT POSITION(B'0' IN B''); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'' IN B''); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'101101' IN B'001011011011011000'); -- 3 position ---------- 3 (1 row) SELECT POSITION(B'10110110' IN B'001011011011010'); -- 3 position ---------- 3 (1 row) SELECT POSITION(B'1011011011011' IN B'001011011011011'); -- 3 position ---------- 3 (1 row) SELECT POSITION(B'1011011011011' IN B'00001011011011011'); -- 5 position ---------- 5 (1 row) SELECT POSITION(B'11101011' IN B'11101011'); -- 1 position ---------- 1 (1 row) SELECT POSITION(B'11101011' IN B'011101011'); -- 2 position ---------- 2 (1 row) SELECT POSITION(B'11101011' IN B'00011101011'); -- 4 position ---------- 4 (1 row) SELECT POSITION(B'11101011' IN B'0000011101011'); -- 6 position ---------- 6 (1 row) SELECT POSITION(B'111010110' IN B'111010110'); -- 1 position ---------- 1 (1 row) SELECT POSITION(B'111010110' IN B'0111010110'); -- 2 position ---------- 2 (1 row) SELECT POSITION(B'111010110' IN B'000111010110'); -- 4 position ---------- 4 (1 row) SELECT POSITION(B'111010110' IN B'00000111010110'); -- 6 position ---------- 6 (1 row) SELECT POSITION(B'111010110' IN B'11101011'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'111010110' IN B'011101011'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'111010110' IN B'00011101011'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'111010110' IN B'0000011101011'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'111010110' IN B'111010110'); -- 1 position ---------- 1 (1 row) SELECT POSITION(B'111010110' IN B'0111010110'); -- 2 position ---------- 2 (1 row) SELECT POSITION(B'111010110' IN B'000111010110'); -- 4 position ---------- 4 (1 row) SELECT POSITION(B'111010110' IN B'00000111010110'); -- 6 position ---------- 6 (1 row) SELECT POSITION(B'111010110' IN B'000001110101111101011'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'111010110' IN B'0000001110101111101011'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'111010110' IN B'000000001110101111101011'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'111010110' IN B'00000000001110101111101011'); -- 0 position ---------- 0 (1 row) SELECT POSITION(B'111010110' IN B'0000011101011111010110'); -- 14 position ---------- 14 (1 row) SELECT POSITION(B'111010110' IN B'00000011101011111010110'); -- 15 position ---------- 15 (1 row) SELECT POSITION(B'111010110' IN B'0000000011101011111010110'); -- 17 position ---------- 17 (1 row) SELECT POSITION(B'111010110' IN B'000000000011101011111010110'); -- 19 position ---------- 19 (1 row) SELECT POSITION(B'000000000011101011111010110' IN B'000000000011101011111010110'); -- 1 position ---------- 1 (1 row) SELECT POSITION(B'00000000011101011111010110' IN B'000000000011101011111010110'); -- 2 position ---------- 2 (1 row) SELECT POSITION(B'0000000000011101011111010110' IN B'000000000011101011111010110'); -- 0 position ---------- 0 (1 row) -- Shifting CREATE TABLE BIT_SHIFT_TABLE(b BIT(16)); INSERT INTO BIT_SHIFT_TABLE VALUES (B'1101100000000000'); INSERT INTO BIT_SHIFT_TABLE SELECT b>>1 FROM BIT_SHIFT_TABLE; INSERT INTO BIT_SHIFT_TABLE SELECT b>>2 FROM BIT_SHIFT_TABLE; INSERT INTO BIT_SHIFT_TABLE SELECT b>>4 FROM BIT_SHIFT_TABLE; INSERT INTO BIT_SHIFT_TABLE SELECT b>>8 FROM BIT_SHIFT_TABLE; SELECT POSITION(B'1101' IN b), POSITION(B'11011' IN b), b FROM BIT_SHIFT_TABLE ; position | position | b ----------+----------+------------------ 1 | 1 | 1101100000000000 2 | 2 | 0110110000000000 3 | 3 | 0011011000000000 4 | 4 | 0001101100000000 5 | 5 | 0000110110000000 6 | 6 | 0000011011000000 7 | 7 | 0000001101100000 8 | 8 | 0000000110110000 9 | 9 | 0000000011011000 10 | 10 | 0000000001101100 11 | 11 | 0000000000110110 12 | 12 | 0000000000011011 13 | 0 | 0000000000001101 0 | 0 | 0000000000000110 0 | 0 | 0000000000000011 0 | 0 | 0000000000000001 (16 rows) SELECT b, b >> 1 AS bsr, b << 1 AS bsl FROM BIT_SHIFT_TABLE ; b | bsr | bsl ------------------+------------------+------------------ 1101100000000000 | 0110110000000000 | 1011000000000000 0110110000000000 | 0011011000000000 | 1101100000000000 0011011000000000 | 0001101100000000 | 0110110000000000 0001101100000000 | 0000110110000000 | 0011011000000000 0000110110000000 | 0000011011000000 | 0001101100000000 0000011011000000 | 0000001101100000 | 0000110110000000 0000001101100000 | 0000000110110000 | 0000011011000000 0000000110110000 | 0000000011011000 | 0000001101100000 0000000011011000 | 0000000001101100 | 0000000110110000 0000000001101100 | 0000000000110110 | 0000000011011000 0000000000110110 | 0000000000011011 | 0000000001101100 0000000000011011 | 0000000000001101 | 0000000000110110 0000000000001101 | 0000000000000110 | 0000000000011010 0000000000000110 | 0000000000000011 | 0000000000001100 0000000000000011 | 0000000000000001 | 0000000000000110 0000000000000001 | 0000000000000000 | 0000000000000010 (16 rows) SELECT b, b >> 8 AS bsr8, b << 8 AS bsl8 FROM BIT_SHIFT_TABLE ; b | bsr8 | bsl8 ------------------+------------------+------------------ 1101100000000000 | 0000000011011000 | 0000000000000000 0110110000000000 | 0000000001101100 | 0000000000000000 0011011000000000 | 0000000000110110 | 0000000000000000 0001101100000000 | 0000000000011011 | 0000000000000000 0000110110000000 | 0000000000001101 | 1000000000000000 0000011011000000 | 0000000000000110 | 1100000000000000 0000001101100000 | 0000000000000011 | 0110000000000000 0000000110110000 | 0000000000000001 | 1011000000000000 0000000011011000 | 0000000000000000 | 1101100000000000 0000000001101100 | 0000000000000000 | 0110110000000000 0000000000110110 | 0000000000000000 | 0011011000000000 0000000000011011 | 0000000000000000 | 0001101100000000 0000000000001101 | 0000000000000000 | 0000110100000000 0000000000000110 | 0000000000000000 | 0000011000000000 0000000000000011 | 0000000000000000 | 0000001100000000 0000000000000001 | 0000000000000000 | 0000000100000000 (16 rows) SELECT b::bit(15), b::bit(15) >> 1 AS bsr, b::bit(15) << 1 AS bsl FROM BIT_SHIFT_TABLE ; b | bsr | bsl -----------------+-----------------+----------------- 110110000000000 | 011011000000000 | 101100000000000 011011000000000 | 001101100000000 | 110110000000000 001101100000000 | 000110110000000 | 011011000000000 000110110000000 | 000011011000000 | 001101100000000 000011011000000 | 000001101100000 | 000110110000000 000001101100000 | 000000110110000 | 000011011000000 000000110110000 | 000000011011000 | 000001101100000 000000011011000 | 000000001101100 | 000000110110000 000000001101100 | 000000000110110 | 000000011011000 000000000110110 | 000000000011011 | 000000001101100 000000000011011 | 000000000001101 | 000000000110110 000000000001101 | 000000000000110 | 000000000011010 000000000000110 | 000000000000011 | 000000000001100 000000000000011 | 000000000000001 | 000000000000110 000000000000001 | 000000000000000 | 000000000000010 000000000000000 | 000000000000000 | 000000000000000 (16 rows) SELECT b::bit(15), b::bit(15) >> 8 AS bsr8, b::bit(15) << 8 AS bsl8 FROM BIT_SHIFT_TABLE ; b | bsr8 | bsl8 -----------------+-----------------+----------------- 110110000000000 | 000000001101100 | 000000000000000 011011000000000 | 000000000110110 | 000000000000000 001101100000000 | 000000000011011 | 000000000000000 000110110000000 | 000000000001101 | 000000000000000 000011011000000 | 000000000000110 | 100000000000000 000001101100000 | 000000000000011 | 110000000000000 000000110110000 | 000000000000001 | 011000000000000 000000011011000 | 000000000000000 | 101100000000000 000000001101100 | 000000000000000 | 110110000000000 000000000110110 | 000000000000000 | 011011000000000 000000000011011 | 000000000000000 | 001101100000000 000000000001101 | 000000000000000 | 000110100000000 000000000000110 | 000000000000000 | 000011000000000 000000000000011 | 000000000000000 | 000001100000000 000000000000001 | 000000000000000 | 000000100000000 000000000000000 | 000000000000000 | 000000000000000 (16 rows) CREATE TABLE VARBIT_SHIFT_TABLE(v BIT VARYING(20)); INSERT INTO VARBIT_SHIFT_TABLE VALUES (B'11011'); INSERT INTO VARBIT_SHIFT_TABLE SELECT CAST(v || B'0' AS BIT VARYING(6)) >>1 FROM VARBIT_SHIFT_TABLE; INSERT INTO VARBIT_SHIFT_TABLE SELECT CAST(v || B'00' AS BIT VARYING(8)) >>2 FROM VARBIT_SHIFT_TABLE; INSERT INTO VARBIT_SHIFT_TABLE SELECT CAST(v || B'0000' AS BIT VARYING(12)) >>4 FROM VARBIT_SHIFT_TABLE; INSERT INTO VARBIT_SHIFT_TABLE SELECT CAST(v || B'00000000' AS BIT VARYING(20)) >>8 FROM VARBIT_SHIFT_TABLE; SELECT POSITION(B'1101' IN v), POSITION(B'11011' IN v), v FROM VARBIT_SHIFT_TABLE ; position | position | v ----------+----------+---------------------- 1 | 1 | 11011 2 | 2 | 011011 3 | 3 | 0011011 4 | 4 | 00011011 5 | 5 | 000011011 6 | 6 | 0000011011 7 | 7 | 00000011011 8 | 8 | 000000011011 9 | 9 | 0000000011011 10 | 10 | 00000000011011 11 | 11 | 000000000011011 12 | 12 | 0000000000011011 13 | 13 | 00000000000011011 14 | 14 | 000000000000011011 15 | 15 | 0000000000000011011 16 | 16 | 00000000000000011011 (16 rows) SELECT v, v >> 1 AS vsr, v << 1 AS vsl FROM VARBIT_SHIFT_TABLE ; v | vsr | vsl ----------------------+----------------------+---------------------- 11011 | 01101 | 10110 011011 | 001101 | 110110 0011011 | 0001101 | 0110110 00011011 | 00001101 | 00110110 000011011 | 000001101 | 000110110 0000011011 | 0000001101 | 0000110110 00000011011 | 00000001101 | 00000110110 000000011011 | 000000001101 | 000000110110 0000000011011 | 0000000001101 | 0000000110110 00000000011011 | 00000000001101 | 00000000110110 000000000011011 | 000000000001101 | 000000000110110 0000000000011011 | 0000000000001101 | 0000000000110110 00000000000011011 | 00000000000001101 | 00000000000110110 000000000000011011 | 000000000000001101 | 000000000000110110 0000000000000011011 | 0000000000000001101 | 0000000000000110110 00000000000000011011 | 00000000000000001101 | 00000000000000110110 (16 rows) SELECT v, v >> 8 AS vsr8, v << 8 AS vsl8 FROM VARBIT_SHIFT_TABLE ; v | vsr8 | vsl8 ----------------------+----------------------+---------------------- 11011 | 00000 | 00000 011011 | 000000 | 000000 0011011 | 0000000 | 0000000 00011011 | 00000000 | 00000000 000011011 | 000000000 | 100000000 0000011011 | 0000000000 | 1100000000 00000011011 | 00000000000 | 01100000000 000000011011 | 000000000000 | 101100000000 0000000011011 | 0000000000000 | 1101100000000 00000000011011 | 00000000000000 | 01101100000000 000000000011011 | 000000000000000 | 001101100000000 0000000000011011 | 0000000000000000 | 0001101100000000 00000000000011011 | 00000000000000000 | 00001101100000000 000000000000011011 | 000000000000000000 | 000001101100000000 0000000000000011011 | 0000000000000000000 | 0000001101100000000 00000000000000011011 | 00000000000000000000 | 00000001101100000000 (16 rows) DROP TABLE BIT_SHIFT_TABLE; DROP TABLE VARBIT_SHIFT_TABLE; -- Get/Set bit SELECT get_bit(B'0101011000100', 10); get_bit --------- 1 (1 row) SELECT set_bit(B'0101011000100100', 15, 1); set_bit ------------------ 0101011000100101 (1 row) SELECT set_bit(B'0101011000100100', 16, 1); -- fail ERROR: bit index 16 out of valid range (0..15) -- Overlay SELECT overlay(B'0101011100' placing '001' from 2 for 3); overlay ------------ 0001011100 (1 row) SELECT overlay(B'0101011100' placing '101' from 6); overlay ------------ 0101010100 (1 row) SELECT overlay(B'0101011100' placing '001' from 11); overlay --------------- 0101011100001 (1 row) SELECT overlay(B'0101011100' placing '001' from 20); overlay --------------- 0101011100001 (1 row) -- This table is intentionally left around to exercise pg_dump/pg_upgrade CREATE TABLE bit_defaults( b1 bit(4) DEFAULT '1001', b2 bit(4) DEFAULT B'0101', b3 bit varying(5) DEFAULT '1001', b4 bit varying(5) DEFAULT B'0101' ); \d bit_defaults Table "public.bit_defaults" Column | Type | Collation | Nullable | Default --------+----------------+-----------+----------+--------------------- b1 | bit(4) | | | '1001'::"bit" b2 | bit(4) | | | '0101'::"bit" b3 | bit varying(5) | | | '1001'::bit varying b4 | bit varying(5) | | | '0101'::"bit" INSERT INTO bit_defaults DEFAULT VALUES; TABLE bit_defaults; b1 | b2 | b3 | b4 ------+------+------+------ 1001 | 0101 | 1001 | 0101 (1 row)