CREATE TABLE [IF NOT EXISTS] table_name( column_definition1, column_definition2, …….., table_constraints ); 也可简写为: CREATE TABLE table_name (column_name column_type); 上述语法的参数说明如下: 以下例子中我们将在 RUNOON 数据库中创建数据...
TheDEFAULTclause specifies a default value for a column. With one exception, the default value must be a constant; it cannot be a function or an expression. This means, for example, that you cannot set the default for a date column to be the value of a function such asNOW()orCURRENT_...
`create_date` datetime DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP COMMENT '创建时间', `update_date` datetime DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP COMMENT'更新时间', 这是建标语句。MySQL 5.5 每个表只允许一个列的默认值根据时间戳生成时间 可以使用触发器来替代一下: CREATE TABLE `example` ( `id`...
Table|Non_unique|Key_name|Seq_in_index|Column_name|Collation|Cardinality|Sub_part|Packed|Null|Index_type|Comment|Index_comment|Visible|Expression|+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+|t1_g|1|t1_g_idx1|1|g|A|NULL|NULL|NULL||SPATIAL|avai...
The CREATE TABLE statement is used to create a table in MySQL. We will create a table named "MyGuests", with five columns: "id", "firstname", "lastname", "email" and "reg_date": CREATE TABLE MyGuests ( id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY, ...
普通租户(MySQL 模式) SQL 语句 CREATE TABLE 更新时间:2025-01-06 14:36:37 编辑 描述 该语句用来在数据库中创建一张新表。 语法 CREATE[TEMPORARY]TABLE[IFNOTEXISTS]table_name(table_definition_list)[table_option_list][partition_option][AS]select;CREATE[TEMPORARY]TABLE[IFNOTEXISTS]table_nameLIKEtable...
LIKE to create an empty table based on the definition of another table, including any column attributes and indexes defined in the original table: CREATE TABLE new_tbl LIKE orig_tbl; For more information, see Section 13.1.18.3, “CREATE TABLE ... LIKE Statement”. [AS] query_expression ...
from table_name [where ...] [order by ...] limit s, n; 从s 开始,筛选 n 条结果,比第二种用法更明确 select ... from table_name [where ...] [order by ...] limit n offset s; 对未知表进行查询时,最好加一条 limit 1,避免因为表中数据过大,查询全表数据导致数据库卡死。
错误原因:本地的mysql版本太低 MySQL 5.5 每个表只允许一个列的默认值根据时间戳生成时间(https://blog.csdn.net/zhangrui1037102215/article/details/79377418) 解决办法:将本地mysql升级成高版本(方法地址:https://blog.csdn.net/chen_lay/article/details/79204312)...
Date: November 17, 2009 08:26AM There is always a primary key. If you do not define one, it will be created for you. Find the hidden $PK column below $ ndb_desc -d test TABLE -- TABLE -- Version: 1 Fragment type: 9 K Value: 6 ...