Question

我无法找到为什么这在MySQL 5.7中无效（用5.7.16测试）

CREATE TABLE TEST_TABLE (ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP);
INSERT INTO TEST_TABLE() VALUES ();
DROP TEMPORARY TABLE IF EXISTS TMP_TEST;
CREATE TEMPORARY TABLE TMP_TEST SELECT * FROM (SELECT ts FROM TEST_TABLE) wrap;

我得到了这个：错误代码：1067。'ts'

的默认值无效

我错过了什么或是mysql错误吗？

Answer 1

我无法重现这个问题。

mysql> SELECT VERSION();
+-----------+
| VERSION() |
+-----------+
| 5.7.16    |
+-----------+
1 row in set (0,00 sec)

mysql> CREATE TABLE TEST_TABLE (ts TIMESTAMP DEFAULT CURRENT_TIMESTAMP);
Query OK, 0 rows affected (0,00 sec)

mysql> INSERT INTO TEST_TABLE() VALUES ();
Query OK, 1 row affected (0,00 sec)

mysql> SELECT * FROM (SELECT ts FROM TEST_TABLE) wrap;
+---------------------+
| ts                  |
+---------------------+
| 2016-11-04 00:00:01 |
+---------------------+
1 row in set (0,00 sec)

mysql> DROP TEMPORARY TABLE IF EXISTS TMP_TEST;
Query OK, 0 rows affected, 1 warning (0,00 sec)

mysql> CREATE TEMPORARY TABLE TMP_TEST;
ERROR 1113 (42000): A table must have at least 1 column

<强>更新

更新问题后：

mysql> SELECT ts FROM TEST_TABLE;
Field   1:  `ts`
Catalog:    `def`
Database:   `test`
Table:      `TEST_TABLE`
Org_table:  `TEST_TABLE`
Type:       TIMESTAMP
Collation:  binary (63)
Length:     19
Max_length: 19
Decimals:   0
Flags:      NOT_NULL BINARY TIMESTAMP 

+---------------------+
| ts                  |
+---------------------+
| 2016-11-04 00:00:01 |
+---------------------+
1 row in set (0,00 sec)

mysql> SELECT * FROM (SELECT ts FROM TEST_TABLE) wrap;
Field   1:  `ts`
Catalog:    `def`
Database:   `test`
Table:      `wrap`
Org_table:  `*`
Type:       TIMESTAMP
Collation:  utf8_general_ci (33)
Length:     57
Max_length: 19
Decimals:   0
Flags:      NOT_NULL BINARY TIMESTAMP 

+---------------------+
| ts                  |
+---------------------+
| 2016-11-04 00:00:01 |
+---------------------+
1 row in set (0,00 sec)

请注意整理的区别。

mysql> CREATE TEMPORARY TABLE TMP_TEST
    -> SELECT * FROM (SELECT BINARY ts FROM TEST_TABLE) wrap;
Query OK, 1 row affected (0,00 sec)
Records: 1  Duplicates: 0  Warnings: 0

更新2

当查询尝试创建临时表时，子查询会将默认值ts列定义为'0000-00-00 00:00:00'，并且必须在变量SQL_MODE中配置服务器{ {1}}值，导致错误。

NO_ZERO_DATE

从mysql> SELECT FIND_IN_SET('NO_ZERO_DATE', @@SQL_MODE); +-----------------------------------------+ | FIND_IN_SET('NO_ZERO_DATE', @@SQL_MODE) | +-----------------------------------------+ | 4 | +-----------------------------------------+ 1 row in set (0,00 sec)删除NO_ZERO_DATE。

SQL_MODE

您可以通过删除子查询来避免此问题。

mysql> SELECT FIND_IN_SET('NO_ZERO_DATE', @@SQL_MODE);
+-----------------------------------------+
| FIND_IN_SET('NO_ZERO_DATE', @@SQL_MODE) |
+-----------------------------------------+
|                                       0 |
+-----------------------------------------+
1 row in set (0,00 sec)

mysql> DROP TEMPORARY TABLE IF EXISTS TMP_TEST;
Query OK, 0 rows affected (0,00 sec)

mysql> CREATE TEMPORARY TABLE TMP_TEST
    -> SELECT * FROM (SELECT ts FROM TEST_TABLE) wrap;
Query OK, 1 row affected (0,00 sec)
Records: 1  Duplicates: 0  Warnings: 0

mysql> SHOW CREATE TABLE TMP_TEST\G
*************************** 1. row ***************************
       Table: TMP_TEST
Create Table: CREATE TEMPORARY TABLE `TMP_TEST` (
  `ts` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00'
) ENGINE=InnoDB
1 row in set (0,00 sec)

timestamp列的默认值无效

1 个答案: