script: select a.TABLE_NAME,a.COLUMN_NAME,a.DATA_TYPE, (CASE a.DATA_TYPE when 'int' then 'limited between -2147483648 and 2147483647' when 'bigint' then 'limited between -9223372036854775808 and 9223372036854775807' when 'smallint' then 'limited betw…

通常情况下,不能向 SQL Server 自增字段插入值,如果非要这么干的话,SQL Server 就会好不客气地给你个错误警告: Server: Msg 544, Level 16, State 1, Line 1 Cannot insert explicit value for identity column in table 't' when identity_insert is set to OFF. 这个错误消息提示我们,如果向 SQL Server 自增字段插入值,需要设置 iden…

If you run into the following error message: An explicit value for the identity column in table '<TABLE_NAME>' can only be specified when a column list is used and IDENTITY_INSERT is ON. It can mean two things. One you've not enabled identity insert…

Identity Column in SQL Server If a column is marked as an identity column, then the values for this column are automatically generated, when you insert a new row into the table. The following, create table statement marks PersonId as an identity colu…

Oracle 12c提供的Identity Column特性简化了自增字段的定义. 声明自增字段通常有3种常见的用法,以下三种方式都支持INSERT语句中省略自增字段的插入,但有些许差别. 1. GENERATED [ALWAYS] AS IDENTITY 此时ALWAYS关键字是可选的: create table tb_test ( id number GENERATED ALWAYS AS IDENTITY, name varchar2(100) ); 此时试图插入指定ID字段的元组将报错,…

--需求有变,需要往t_login表的f_userName字段添加外国人名,之前设置的varchar(10)不够,商议决定改成varchar(30),执行的时候,提示消息 索引'uq_f_userName' 依赖于 列'f_userName'.由于一个或多个对象访问此列,ALTER TABLE ALTER COLUMN f_userName 失败.--原来,之前为了防止f_userName重复,添加了唯一索引uq_f_userName.--进行如下操作后,问题妥妥解决--表名:t_login(登…

Alter Table/Partition/Column Alter Table Rename Table Alter Table Properties Alter Table Comment Add SerDe Properties Alter Table Storage Properties Additional Alter Table Statements Alter Partition Add Partitions Dynamic Partitions Rename Partition…

mysql -A不预读数据库信息(use dbname 更快)—Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A 出现问题的原因是::        我们进入mysql 时,没有使用-A参数:        即我们使用            mysql -hhostname -uusern…

mysql -A不预读数据库信息(use dbname 更快)—Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A mysql> use dbname Reading table information for completion of table and column names You…

mysql> use ad_detail_page;Reading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with -A…