REFERENCEStable-name(,column-name) ON DELETE NO ACTIONON DELETERESTRICTCASCADESET NULLSET DEFAULT ON UPDATE NO ACTIONON UPDATE RESTRICT6 check-constraint CONSTRAINTconstraint-nameCHECK(check-condition ) ON INSERT VIOLATION SETcolumn-name = DEFAULTON UPDATE VIOLATION PRESERVEcolumn-name7 period-definiti...
ALTER TABLE modifies a table definition by altering, adding, or dropping columns and constraints. ALTER TABLE also reassigns and rebuilds partitions, or disables and enables constraints and triggers.
Alter Table add Column - How do you add a column after say the second column Alter table add constraint primary key clustered identity(1,1) ALTER TABLE ALTER COLUMN (To set the default value) ALTER TABLE Progress? ALTER TABLE SWITCH statement failed. Check constraints or partition function o...
You can't alter the existing columns for identity. You have 2 options, 1. Create a new table with identity & drop the existing table 2. Create a new column with identity & drop the existing column But take spl care when these columns have any constraints / relations. Code Snippet /* F...
However, if you add an identity column to a table that is not empty, the table space is placed in REORG-pending (REORP) status.The table must not be a history table or archive table.If the table is a system-period temporal table, the column is also added to the associated history ...
★自动生成的列,不能通过alter table语句修改为序列值,换句话说,序列只能在定义表的时候指定。 db2 => create table test2(id integer generated always as identity,sex char(1) check (sex in ('F','M'))) DB20000I SQL 命令成功完成。 db2 => alter table test2 add column name varchar(20) with ...
CREATE TABLE tauto(i INT GENERATED BY DEFAULT AS IDENTITY, k INT) CREATE UNIQUE INDEX tautoInd ON tauto(i) INSERT INTO tauto(k) values 1,2 The system will automatically generate values for the identity column. But now you need to manually insert some data into the identity column: ...
IDENTITY Indicates that the new column is an identity column. When a new row is added to the table, Microsoft SQL Server Compact 3.5 (SQL Server Compact 3.5) provides an incremental value for the column. Identity columns are typically used in conjunction with PRIMARY KEY constraints to serve ...
第二章 SQL命令 ALTER TABLE(二) 删除列限制 DROP COLUMN可以删除指定为逗号分隔列表的多个列定义。每个列出的列名后面必须紧跟其RESTORY或CASCADE(如果未指定,则默认为RESTRICE)和%DELDATA或%NODELDATE(如果未指定,则默认为%NODELDATA)选项。 默认情况下,删除列定义不会从数据映射中删除存储在该列中的任何数据。
第二章 SQL命令 ALTER TABLE(二) 删除列限制 DROP COLUMN可以删除指定为逗号分隔列表的多个列定义。每个列出的列名后面必须紧跟其RESTORY或CASCADE(如果未指定,则默认为RESTRICE)和%DELDATA或%NODELDATE(如果未指定,则默认为%NODELDATA)选项。 默认情况下,删除列定义不会从数据映射中删除存储在该列中的任何数据。