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if (exists (select * from sys.databases where name = 'testHome')) drop database testHomegocreate database testHome--默認(rèn)就屬于primary主文件組，可省略on primary ( --數(shù)據(jù)文件的具體描述 name = 'testHome_data', --主數(shù)據(jù)文件的邏輯名 fileName = 'c:\testHome_data.mdf', --主數(shù)據(jù)文件的物理名 size = 3MB, --主數(shù)據(jù)文件的初始大小 maxSize = 50MB, --主數(shù)據(jù)文件增長(zhǎng)的最大值 fileGrowth = 10% --主數(shù)據(jù)文件的增長(zhǎng)率)--日志文件的具體描述，各參數(shù)含義同上log on ( name = 'testHome_log', fileName = 'c:\testHome_log.ldf', size = 1MB, fileGrowth = 1MB)go方法3（設(shè)置次數(shù)據(jù)文件）、if (exists (select * from sys.databases where name = 'testHome')) drop database testHomegocreate database testHome--默認(rèn)就屬于primary主文件組，可省略on primary ( --數(shù)據(jù)文件的具體描述 name = 'testHome_data', --主數(shù)據(jù)文件的邏輯名 fileName = 'c:\testHome_data.mdf', --主數(shù)據(jù)文件的物理名 size = 3MB, --主數(shù)據(jù)文件的初始大小 maxSize = 50MB, --主數(shù)據(jù)文件增長(zhǎng)的最大值 fileGrowth = 10% --主數(shù)據(jù)文件的增長(zhǎng)率),--次數(shù)據(jù)文件的具體描述( --數(shù)據(jù)文件的具體描述 name = 'testHome2_data', --主數(shù)據(jù)文件的邏輯名 fileName = 'c:\testHome2_data.mdf', --主數(shù)據(jù)文件的物理名 size = 2MB, --主數(shù)據(jù)文件的初始大小 maxSize = 50MB, --主數(shù)據(jù)文件增長(zhǎng)的最大值 fileGrowth = 10% --主數(shù)據(jù)文件的增長(zhǎng)率)--日志文件的具體描述，各參數(shù)含義同上log on ( name = 'testHome_log', fileName = 'c:\testHome_log.ldf', size = 1MB, fileGrowth = 1MB),( name = 'testHome2_log', fileName = 'c:\testHome2_log.ldf', size = 1MB, fileGrowth = 1MB)go基本數(shù)據(jù)類型精確數(shù)字類型類型描述bigintbigint 數(shù)據(jù)類型用于整數(shù)值可能超過(guò) int 數(shù)據(jù)類型支持范圍的情況，范圍：-2^63 到 2^63-1，存儲(chǔ)空間8字節(jié)int整數(shù)數(shù)據(jù)類型，范圍在-2^31 到 2^31-1，存儲(chǔ)空間4字節(jié)smallint整數(shù)，范圍在-2^15 到 2^15-1，存儲(chǔ)空間2字節(jié)tinyint范圍在0 到 255，存儲(chǔ)空間1字節(jié)bit可以取值為 1、0 或 NULL 的整數(shù)數(shù)據(jù)類型，每8個(gè)bit占一個(gè)字節(jié)，16bit就2個(gè)字節(jié)，24bit就3個(gè)字節(jié)decimal帶固定精度和小數(shù)位數(shù)的數(shù)值數(shù)據(jù)類型，有效值從 - 10^38 +1 到 10^38 - 1numeric同上money貨幣或貨幣值的數(shù)據(jù)類型，范圍在-922,337,203,685,477.5808 到 922,337,203,685,477.5807smallmoney貨幣類型，-214,748.3648 到 214,748.3647近似數(shù)字類型類型描述float表示浮點(diǎn)數(shù)值數(shù)據(jù)的大致數(shù)值數(shù)據(jù)類型。浮點(diǎn)數(shù)據(jù)為近似值；范圍-1.79E + 308 至 -2.23E - 308、0 以及 2.23E - 308 至 1.79E + 308realreal 的 SQL-92 同義詞為 float(24)，范圍在-3.40E + 38 至 -1.18E - 38、0 以及 1.18E - 38 至 3.40E + 38日期時(shí)間類型類型描述datetime表示某天的日期和時(shí)間的數(shù)據(jù)類型，范圍在1753 年 1 月 1 日到 9999 年 12 月 31 日smalldatetime范圍在1900 年 1 月 1 日到 2079 年 6 月 6 日字符串類型類型描述char固定長(zhǎng)度或可變長(zhǎng)度的字符數(shù)據(jù)類型，范圍在范圍為 1 至 8,000字節(jié)text最大長(zhǎng)度為 2^31-1varchar固定長(zhǎng)度或可變長(zhǎng)度的字符數(shù)據(jù)類型，最大存儲(chǔ)大小是 2^31-1 個(gè)字節(jié)Unicode字符串類型類型描述nchar字符數(shù)據(jù)類型，長(zhǎng)度固定，在必須在 1 到 4,000 之間nvarchar可變長(zhǎng)度 Unicode 字符數(shù)據(jù)。最大存儲(chǔ)大小為 2^31-1 字節(jié)ntext長(zhǎng)度可變的 Unicode 數(shù)據(jù)，最大長(zhǎng)度為 2^30 - 1 (1,073,741,823) 個(gè)字符二進(jìn)制字符串類型類型描述binary長(zhǎng)度為 n 字節(jié)的固定長(zhǎng)度二進(jìn)制數(shù)據(jù)，范圍從 1 到 8,000 的值。存儲(chǔ)大小為 n 字節(jié)。varbinary可變長(zhǎng)度二進(jìn)制數(shù)據(jù)。n 可以取從 1 到 8,000 的值。最大的存儲(chǔ)大小為 2^31-1 字節(jié)image長(zhǎng)度可變的二進(jìn)制數(shù)據(jù)，從 0 到 2^31-1 (2,147,483,647) 個(gè)字節(jié)判斷表或其他對(duì)象及列是否存在--判斷某個(gè)表或?qū)ο笫欠翊嬖趇f (exists (select * from sys.objects where name = 'classes')) print '存在';goif (exists (select * from sys.objects where object_id = object_id('student'))) print '存在';goif (object_id('student', 'U') is not null) print '存在';go --判斷該列名是否存在，如果存在就刪除if (exists (select * from sys.columns where object_id = object_id('student') and name = 'idCard')) alter table student drop column idCardgoif (exists (select * from information_schema.columns where table_name = 'student' and column_name = 'tel')) alter table student drop column telgo創(chuàng)建、刪除表--判斷是否存在當(dāng)前tableif (exists (select * from sys.objects where name = 'classes')) drop table classesgocreate table classes( id int primary key identity(1, 2), name varchar(22) not null, createDate datetime default getDate())goif (exists (select * from sys.objects where object_id = object_id('student'))) drop table studentgo--創(chuàng)建tablecreate table student( id int identity(1, 1) not null, name varchar(20), age int, sex bit, cid int)go給表添加字段、修改字段、刪除字段--添加字段alter table student add address varchar(50) not null;--修改字段alter table student alter column address varchar(20);--刪除字段alter table student drop column number; --添加多個(gè)字段alter table student add address varchar(22), tel varchar(11), idCard varchar(3); --判斷該列名是否存在，如果存在就刪除if (exists (select * from sys.columns where object_id = object_id('student') and name = 'idCard')) alter table student drop column idCardgoif (exists (select * from information_schema.columns where table_name = 'student' and column_name = 'tel')) alter table student drop column telgo添加、刪除約束--添加新列、約束alter table student add number varchar(20) null constraint no_uk unique; --增加主鍵alter table student add constraint pk_id primary key(id); --添加外鍵約束alter table student add constraint fk_cid foreign key (cid) references classes(id)go--添加唯一約束alter table student add constraint name_uk unique(name);--添加check約束alter table student with nocheck add constraint check_age check (age > 1);alter table student add constraint ck_age check (age >= 15 and age <= 50)--添加默認(rèn)約束alter table student add constraint sex_def default 1 for sex;--添加一個(gè)包含默認(rèn)值可以為空的列alter table student add createDate smalldatetime null constraint createDate_def default getDate() with values; ----- 多個(gè)列、約束一起創(chuàng)建--------alter table student add /*添加id主鍵、自增*/ id int identity constraint id primary key, /* 添加外鍵約束*/ number int null constraint uNumber references classes(number), /*默認(rèn)約束*/ createDate decimal(3, 3) constraint createDate default 2010-6-1 go  --刪除約束alter table student drop constraint no_uk;插入數(shù)據(jù)insert into classes(name) values('1班');insert into classes values('2班', '2011-06-15');insert into classes(name) values('3班');insert into classes values('4班', default); insert into student values('zhangsan', 22, 1, 1);insert into student values('lisi', 25, 0, 1);insert into student values('wangwu', 24, 1, 3);insert into student values('zhaoliu', 23, 0, 3);insert into student values('mazi', 21, 1, 5);insert into student values('wangmazi', 28, 0, 5);insert into student values('jason', null, 0, 5);insert into student values(null, null, 0, 5); insert into student select 'bulise' name, age, sex, cid from student where name = 'tony'; --多條記錄同時(shí)插入insert into student select 'jack', 23, 1, 5 union select 'tom', 24, 0, 3 union select 'wendy', 25, 1, 3 union select 'tony', 26, 0, 5;查詢、修改、刪除數(shù)據(jù)--查詢數(shù)據(jù)select * from classes;select * from student;select id, 'bulise' name, age, sex, cid from student where name = 'tony';select *, (select max(age) from student) from student where name = 'tony'; --修改數(shù)據(jù)update student set name = 'hoho', sex = 1 where id = 1; --刪除數(shù)據(jù)（from可省略）delete from student where id = 1;備份數(shù)據(jù)、表--備份、復(fù)制student表到stuselect * into stu from student;select * into stu1 from (select * from stu) t;select * from stu;select * from stu1;利用存儲(chǔ)過(guò)程查詢表信息--查詢student相關(guān)信息exec sp_help student;exec sp_help classes;