拼接sql语句
Ⅰ 多条sql语句如何拼接
SQL语句拼接一般使用【union all】和【union】
两者的区别是:
【union all】:显示多条语句里的全部记录;
【union】:显示多条语句里的不重复的记录,也就是有DIstinct的功效;
【union all】示例:
select'2016-02-06'date_timeunionall
select'2016-02-14'unionall
select'2016-06-12'unionall
select'2016-09-18'unionall
select'2016-10-09'unionall
select'2016-10-09'
结果为6行
【union】示例:
select'2016-02-06'date_timeunionall
select'2016-02-14'unionall
select'2016-06-12'unionall
select'2016-09-18'unionall
select'2016-10-09'unionall
select'2016-10-09'
结果为5行
Ⅱ 新手:拼接sql语句求改带参数的sql语句
string sql= "SELECT count(*) from Logs where UserName=@username and Passwrod=
@password“;
SqlConnection conn=new SqlConnection (constr);//constr是数据库连接字符串,要自己写的,
SqlCommand cmd=new SqlCommand(sql,conn);
SqlParameter p1 = new SqlParameter("@username", username);
SqlParameter p2 = new SqlParameter("@password", password);
cmd.Parameters.Add(p1);
cmd.Parameters.Add(p2);
//这样就可以了,@username,@password是SQL中的命令参数,username,password是应用程序的参数
Ⅲ SQL语句拼接
在原来的基础上加上一句
selectQ.*,
row_number()over(orderbya.viddesc)rn
fromtb_QuestionQinnerjoin(
selectTOP100PERCENTQuestionID,MAX(VoteNice)asVidfromtb_AnswerA
groupbyQuestionIDorderbyMAX(VoteNice))T
onQ.QuestionID=T.QuestionIDorderbyT.Vid
Ⅳ jdbc怎么拼接sql语句
在jdbc中,有三种方式执行sql,分别是使用Statement(sql拼接),PreparedStatement(预编译),还有一种CallableStatement(存储过程),在这里我就不介绍CallableStatement了,我们来看看Statement与PreparedStatement的区别。
Ⅳ sql server 怎样拼接sql语句
/*定义变量,然后赋值就可以拼接sql脚本了*/
declare@sqlvarchar(max)
set@sql='select*fromsysobjects'
set@sql=@sql+'wherextype=''u'''
exec(@sql)
Ⅵ 拼接SQL语句
sql语句拼接主要操作于条件增加删除修改或查询面给介绍条件查询例:
既拼接sql语句度定用StringBuffer修饰用String
String name=request.getParameter("name");
String address=request.getParemeter("address");
StringBuffer sql = new StringBuffer();
sql.append("select * from Tuser as t where 1=1");
if(name!=null||!"".equals(name)){
sql.append(" and t.name like'%"+name+"%'");
}
if(address!=null||!"".equals(address)){
sql.append(" and t.address like'%"+address+"%'");
}
拼接sql语句说select * from Tuser as t where 1=1定执行面两根据用户数据参数选择执行
我手写啊没复制明白明再问我明白给吧嘿嘿!
Ⅶ 两个sql语句拼接
select m.khmc,m.djr,m.bfrq, m.bfr,m.bfmd,m.fkqk from formtable_main_32 m ,(
select id,mc,gjc from (select id,mc mc,ywgjz gjc from formtable_main_23 where cyfl = 4 union
select id,tzr mc,tzrxssjg gjc from formtable_main_23 where cyfl = 0 union
select id,Yfjsfzr mc,Yfxx gjc from formtable_main_23 where cyfl = 1 union
select id,Lshi mc,Lsuo gjc from formtable_main_23 where cyfl = 2 union
select a.id,Rczw mc,b.selectname gjc from formtable_main_23 a left join workflow_SelectItem b on a.Rchy = b.selectvalue where cyfl = 3 and fieldid = 6212) as tmp) tm where m.id=tm.id
Ⅷ java如何拼接sql语句
你咋不试试,
String columnStr;
String valueStr;
for(int i=0; i<columns.length; i++){
columnStr = "(" + columns[i] + ",";
valueStr = "'( \"" + value[i] + ",";
}
参考JAVA转义字符。网络一下吧。你自己试试,我这里没装jdk,懒得弄了,准备休息了。
Ⅸ 如何实现sql语句的拼接
declare @sql varchar(500)
set @sql ='SELECT * FROM TABLE1'
set @sql = @sql + ' WHERE PRICE>20.00'
set @sql = @sql + ' AND COUNTS>5000'
set @sql = @sql + ' ORDER BY COUNTS DESC'
Ⅹ sql查询语句怎么拼接字符串
--1、在where的地方可以用case
select*
from表1
where字段1=casewhen@字段1>0then@字段1end
--2、或者在赋值的时候做判断用4个参数,你可以根据下面的写法自己修改
@字段1,@字段2,@字段3,@字段
if@字段1>0
begin
select@字段=@字段1
select*
from表1
where字段1=@字段
end
ifif@字段1<0and@@字段2>0
begin
select@字段=@字段2
select*
from表1
where字段1=@字段
end