1 ALTER 表名 table1 ALTER COLUMN [字段] 类型 NULL; 2 3 例如: 4 ALTER TABLE tb_guest ALTER COLUMN [ROOM_CODE] [nvarchar] (50) COLLATE Chinese_PRC_CI_AS NULL;
AlterTableAddTableElementStatement AlterTableAlterColumnOption AlterTableAlterColumnStatement AlterTableAlterIndexStatement AlterTableAlterPartitionStatement AlterTableChangeTrackingModificationStatement AlterTableConstraintModificationStatement AlterTableDropTableElement AlterTableDropTableElementStatement AlterTableFileTableName...
create table Student ( stuid varchar(10) null, Sneme varchar (20) not null, Sage int not null, Ssex char(10) not null ) --给表增加自增 stuid列 alter table student drop column [stuid ] --删除原来的stuid不是自增的字段 --表student新增 [stuid]列并设为自增,类型为int alter table stu...
AlterTableAddTableElementStatement AlterTableAlterColumnOption AlterTableAlterColumnStatement AlterTableAlterIndexStatement AlterTableAlterPartitionStatement AlterTableChangeTrackingModificationStatement AlterTableConstraintModificationStatement AlterTableDropTableElement AlterTableDropTableElementStatement AlterTableFile...
AlterTableAddTableElementStatement AlterTableAlterColumnOption AlterTableAlterColumnStatement AlterTableAlterIndexStatement AlterTableAlterPartitionStatement AlterTableChangeTrackingModificationStatement AlterTableConstraintModificationStatement AlterTableDropTableElement AlterTableDropTableElementStatement AlterTableFileTableNam...
AlterTableAddTableElementStatement AlterTableAlterColumnOption AlterTableAlterColumnStatement AlterTableAlterIndexStatement AlterTableAlterPartitionStatement AlterTableChangeTrackingModificationStatement AlterTableConstraintModificationStatement AlterTableDropTableElement AlterTableDropTableElementStatement AlterTableFileTableName...
ALTER TABLE xxx ADD actobj_count NUMERIC(3) NULL; EXECUTE sp_addextendedproperty N'MS_Description', N'该活动下的活动对象个数', N'user', N'dbo', N'table', N'gl_activity', N'column', N'actobj_count'; ALTER TABLE gl_activity_customer DROP COLUMN has_statistics; ...
Oracleでは、SQL文の空の文字列がnull値として処理されます。SQL Serverは、空の文字列を空の文字列として処理します。 空の文字列を比較すると、ゲートウェイは変換せずに文字通り空の文字列をSQL Serverデータベースに渡します。空の文字列がNULL値を表すことを意図していた場合、SQL Serverはそ...
rc2 rcpackage.rctype; rec2 loc_dept%rowtype; rc3 rcpackage.rctype; rec3 outargs%rowtype; out_arg varchar2(255); begin -- Execute procedure out_arg := null; refcurproc@MSQL('Hello World', out_arg, rc1); -- Fetch 20 rows from the remote emp table and insert them into loc_emp...
AlterTableAddTableElementStatement AlterTableAlterColumnOption AlterTableAlterColumnStatement AlterTableAlterIndexStatement AlterTableAlterPartitionStatement AlterTableChangeTrackingModificationStatement AlterTableConstraintModificationStatement AlterTableDropTableElement AlterTableDropTableElementStatement AlterTableFileTableName...