CREATE DATABASE Test
( ):
DROP DATABASE Test
, , :
USE Test
Test SSMS. .
, :
CREATE TABLE [](
[ ] int,
[] nvarchar (30),
[ ] date,
[ E -mail] nvarchar (30),
[] nvarchar (30),
[] nvarchar (30)
)
[].
. MS SQL , , , PersonnelNumber. , , PhoneNumber1.
PHONE_NUMBER, , ORACLE. .
[]:
DROP TABLE []
, Employees, :
ID ( )
Name
Birthday
Email E-mail
Position
Department
ID.
:
CREATE TABLE Employees(
ID int,
Name nvarchar (30),
Birthday date,
Email nvarchar (30),
Position nvarchar (30),
Department nvarchar (30)
)
, , NOT NULL.
:
-- ID
ALTER TABLE Employees ALTER COLUMN ID int NOT NULL
-- Name
ALTER TABLE Employees ALTER COLUMN Name nvarchar (30) NOT NULL
SQL ( , , ). DDL ( , ), SQL (.. , , , ). SQL , .. , .. .
|
|
, ORACLE:
--
CREATE TABLE Employees(
ID int, -- ORACLE int - () number(38)
Name nvarchar2 (30), -- nvarchar2 ORACLE nvarchar MS SQL
Birthday date,
Email nvarchar2 (30),
Position nvarchar2 (30),
Department nvarchar2 (30)
);
-- ID Name ( ALTER COLUMN MODIFY())
ALTER TABLE Employees MODIFY (ID int NOT NULL, Name nvarchar2 (30) NOT NULL);
-- PK ( MS SQL, )
ALTER TABLE Employees ADD CONSTRAINT PK_Employees PRIMARY KEY (ID);
ORACLE varchar2, , , UTF-8. ORACLE , , BYTE CHAR, , :
NAME varchar2(30 BYTE) -- 30
NAME varchar2(30 CHAR) -- 30
BYTE CHAR, ORACLE varchar2(30), , IDE. , ORACLE, varchar2 ( , , UTF-8) CHAR (.. ).
- , , ID Name . , ID, Position Department, :
INSERT Employees(ID,Position,Department) VALUES
(1000, N '', N ''),
(1001, N '', N ''),
(1002, N '', N ''),
(1003, N ' ', N '')
, INSERT , .. Name.
, , ALTER TABLE Employees ALTER COLUMN ID int NOT NULL , ALTER TABLE Employees ALTER COLUMN Name int NOT NULL , Name NULL ( ) .
Name :