CreateDate INT UNSIGNED NOT NULL DEFAULT UNIX_TIMESTAMP(), Primary Key (Table1ID) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; Navigate:Previous Message•Next Message Options:Reply•Quote Subject Views Written By Posted Create table with default value unix_timestamp ...
default是作用在用户忽略了这一列的时候,如果设置了使用默认值,如果没有设置,直接报错。 如果我们在建表时没有设置默认值,mysql会对我们的表进行优化。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 mysql> create table t14( -> name varchar(20), -> age varchar(20) -> ); Query OK, 0 rows ...
mysql>CREATETABLEt1(aINT,bINT);QueryOK,0rowsaffected(0.06sec)mysql>SELECTtable_id,name,instant_colsFROMinformation_schema.innodb_tablesWHEREnameLIKE'%t1%';+---+---+---+|table_id|name|instant_cols|+---+---+---+|1065|test/t1|0|+---+---+---+1rowinset(0.22sec)mysql>SELECTtable_...
1、创建表(create table) ㈠ 语法格式 powershell create table 表名 (字段1,字段2,...) create table 表名 (字段1数据类型(字符长度),字段2,...) create table 表名 (字段1数据类型(字符长度) 约束条件,字段2,...) ㈡ 示例 powershell 创建t1表,id列整型,name列字符串 int(10) varchar(30) creat...
CREATE TABLE creates a table with the given name. You must have the CREATE privilege for the table. By default, tables are created in the default database, using the InnoDB storage engine. An error occurs if the table exists, if there is no default database, or if the database does ...
default value ===default=== #设置id字段有默认值后,则无论id字段是null还是not null,都可以插入空,插入空默认填入default指定的默认值 mysql> create table t3(id int default 1); mysql> alter table t3 modify id int not null default 1; ===综合练习=== mysql> create table student( -> name va...
`sex` VARCHAR(1) NOT NULL DEFAULT'男' COMMENT'sex', PRIMARY KEY(`id`) )ENGINE=INNODB DEFAULT CHARSET=utf8 1. 2. 3. 4. 5. 6. 7. 格式 AI检测代码解析 create table [if not exists] `表的名称`(--创建格式 `列的名字` 列的类型(长度) [属性] [索引] [注释], ...
CREATE TABLE creates a table with the given name. You must have theCREATE privilege for the table.By default, tables are created in the default database, using theInnoDB storage engine. An error occurs if the table exists, if there isno default database, or if the database does not ...
When inserting a new row, the default value for a column with an expression default can be inserted either by omitting the column name or by specifying the column asDEFAULT(just as for columns with literal defaults): mysql>CREATETABLEt4(uidBINARY(16)DEFAULT(UUID_TO_BIN(UUID()));mysql>INSER...
由于该参数首先被设置,所以这部分计算逻辑所取用的变量均来自配置文件中的设置值(源码中的table_cache_size对应配置文件中的table_open_cache),根据计算后得出的limit_1,2,3将取最大值存放在变量request_open_files中。 PS:此处需注意的是,request_open_files和requested_open_files是不同的。