パターン 1
CAST 構文 1
SELECT CAST('0123456789' AS SMALLINT)
Invalid operation: value "0123456789" is out of range for type smallint;
SELECT CAST('0123456789' AS INTEGER)
int4
123456789
SELECT CAST('0123456789' AS BIGINT)
int8
123456789
SELECT CAST('0123456789' AS DECIMAL)
numeric
123456789
SELECT CAST('0123456789' AS REAL)
float4
1.23456792E8
SELECT CAST('0123456789' AS DOUBLE PRECISION)
float8
1.23456789E8
SELECT CAST('0' AS BOOLEAN)
bool
false
SELECT CAST('1' AS BOOLEAN)
bool
true
SELECT CAST(0123456789 AS CHAR)
bpchar
1
SELECT CAST(0123456789 AS VARCHAR)
varchar
123456789
SELECT CAST('2015-02-23 23:22:22' AS DATE)
date
2015-02-23
SELECT CAST('2015-02-23 23:22:22' AS TIMESTAMP)
timestamp
2015-02-23 23:22:22.000000
SELECT CAST('2015-02-23 23:22:22' AS TIMESTAMPTZ)
timestamptz
2015-02-23 23:22:22+00パターン 2
CAST 構文 2
SELECT '0123456789'::SMALLINT
Invalid operation: value "0123456789" is out of range for type smallint;
SELECT '0123456789'::INTEGER
int4
123456789
SELECT '0123456789'::BIGINT
int8
123456789
SELECT '0123456789'::DECIMAL
numeric
123456789
SELECT '0123456789'::REAL
float4
1.23456792E8
SELECT '0123456789'::DOUBLE PRECISION
float8
1.23456789E8
SELECT '0'::BOOLEAN
bool
false
SELECT '1'::BOOLEAN
bool
true
SELECT 0123456789::CHAR
bpchar
1
SELECT 0123456789::VARCHAR
varchar
123456789
SELECT '2015-02-23 23:22:22'::DATE
date
2015-02-23
SELECT '2015-02-23 23:22:22'::TIMESTAMP
timestamp
2015-02-23 23:22:22.000000
SELECT '2015-02-23 23:22:22'::TIMESTAMPTZ
timestamptz
2015-02-23 23:22:22+00