Postgres 16

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-- 测试数据组 1
SELECT CAST('12345' AS INTEGER) AS result;
SELECT CAST('000123' AS INTEGER) AS result;
SELECT CAST('00000' AS INTEGER) AS result;

result

12345

SELECT 1

result

123

SELECT 1

result

0

SELECT 1

-- 测试数据组 2
SELECT CAST('abc' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "abc"
LINE 2: SELECT CAST('abc' AS INTEGER) AS result;
                    ^

SELECT CAST('123abc' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "123abc"
LINE 1: SELECT CAST('123abc' AS INTEGER) AS result;
                    ^

SELECT CAST('000abc' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "000abc"
LINE 1: SELECT CAST('000abc' AS INTEGER) AS result;
                    ^

-- 测试数据组 3
SELECT CAST('abc.' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "abc."
LINE 2: SELECT CAST('abc.' AS INTEGER) AS result;
                    ^

SELECT CAST('3.abc' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "3.abc"
LINE 1: SELECT CAST('3.abc' AS INTEGER) AS result;
                    ^

-- 测试数据组 4
SELECT CAST('123.000' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "123.000"
LINE 2: SELECT CAST('123.000' AS INTEGER) AS result;
                    ^

SELECT CAST('123.123000' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "123.123000"
LINE 1: SELECT CAST('123.123000' AS INTEGER) AS result;
                    ^

-- 测试数据组 5
SELECT CAST('28937198379809271983123117989712938123' AS INTEGER) AS result;

ERROR:  value "28937198379809271983123117989712938123" is out of range for type integer
LINE 2: SELECT CAST('28937198379809271983123117989712938123' AS INTE...
                    ^

SELECT CAST('-8621367813698137981738917238918939781231231' AS INTEGER) AS result;

ERROR:  value "-8621367813698137981738917238918939781231231" is out of range for type integer
LINE 1: SELECT CAST('-8621367813698137981738917238918939781231231' A...
                    ^

-- 测试数据组 6
SELECT CAST('e3' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "e3"
LINE 2: SELECT CAST('e3' AS INTEGER) AS result;
                    ^

SELECT CAST('abc' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "abc"
LINE 1: SELECT CAST('abc' AS INTEGER) AS result;
                    ^

SELECT CAST('1.234e5' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "1.234e5"
LINE 1: SELECT CAST('1.234e5' AS INTEGER) AS result;
                    ^

SELECT CAST('12345e-2' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "12345e-2"
LINE 1: SELECT CAST('12345e-2' AS INTEGER) AS result;
                    ^

SELECT CAST('e3' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "e3"
LINE 1: SELECT CAST('e3' AS INTEGER) AS result;
                    ^

SELECT CAST('0e3' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "0e3"
LINE 1: SELECT CAST('0e3' AS INTEGER) AS result;
                    ^

SELECT CAST('1e3' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: "1e3"
LINE 1: SELECT CAST('1e3' AS INTEGER) AS result;
                    ^

-- 测试数据组 7
SELECT CAST('.0000000' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: ".0000000"
LINE 3: SELECT CAST('.0000000' AS INTEGER) AS result;
                    ^

SELECT CAST('.123456' AS INTEGER) AS result;

ERROR:  invalid input syntax for type integer: ".123456"
LINE 1: SELECT CAST('.123456' AS INTEGER) AS result;
                    ^