Introducing Substring in SQL Substring is commonly defined as a function that is utilized to return a segment of a string. Different databases follow different means of doing so. For instance, in ORACLE, the function is SUBSTR(), in MYSQL, it is SUBSTR(), SUBSTRING(), and in the SQL ser...
Select*from学生表whereleft(姓名,1)=’杨’orleft(姓名,1)=’张’orleft(姓名,1)=’李’Select*from学生表whereleft(姓名,1)in(’杨’,’张’,’李’)Select*from学生表whereleft(姓名,1)like'[杨张李]'Select*from学生表where姓名like'[杨张李]%'Select*from学生表wheresubstring(姓名,1,1)like'[杨...
bstring 有两种，一种在.net中，一种在SQL中。SQL中：substring("abcdefg",4,2)返回的值为：ef 从字符串"abcdefg"中第4位开始取2位。是.net中的：第二个参数长度。"abcdefg".substring(4,2)返回的值为：ef 从字符串"abcdefg"中第4位开始取，取到第2位。"abcdefg".substring(4)返回：efg ...
substring_index(substring_index(str,'.',-2),'.',1); sql中字符串的切割、截取、删除、替换、计算字符串的长度函数# select-- 替换法 replace(string,'被替换部分','替换后的结果') -- device_id, replace(blog_url,'http:/url/','')asuser_name -- 截取法 substr(string, start_point, length*...
CustomName包含客户的First Name和Last Name,它们之间被一个空格隔开。我们用CHARINDX函数确定两个名字中间空格的位置。通过这个方法,我们可以分析ContactName列的空格位置,这样可以只显示这个列的last name部分。 select top 5 substring(ContactName,charindex(‘‘,ContactName)+1,len(ContactName)) as [Last Name]...
I started SQL recently as a beginner i came across the above problem. the book i referring is using MySQL and i want to know how can i do the following in SQL Server This is the query as per the example in the book SELECT SUBSTRING_INDEX(location, ',', 1) FROM my_contacts; ...
SQL IF EXISTS (SELECTtable_nameFROMINFORMATION_SCHEMA.TABLESWHEREtable_name ='npub_info')DROPTABLEnpub_info; GO-- Create npub_info table in pubs database. Borrowed from instpubs.sql.USEpubs; GOCREATETABLEnpub_info ( pub_idCHAR(4)NOTNULLREFERENCESpublishers(pub_id)CONSTRAINTUPKCL_npubinfo ...
在PostgreSQL(简称pgsql)中,SUBSTRING函数是一个非常强大的工具,用于从字符串中提取子串。这个函数不仅支持基础的字符串截取操作,还支持使用正则表达式进行复杂的模式匹配。本文将详细探讨SUBSTRING函数的不同用法,并通过丰富的代码样例展示其在实际应用中的灵活性。
This article explains the functionality and uses of the LEFT, RIGHT, SUBSTRING and CHARINDEX functions in SQL. This article will leave you with sound knowledge and understanding that you can take away and questions will be asked no more. ...
6)locate(substr,str) 、position(substr in str) :返回子串substr在字符串str第一个出现的位置,如果substr不是在str里面,返回0。 locate(substr,str,pos),返回子串substr在字符串str第一个出现的位置,从位置pos开始。如果substr不是在str里面,返回0。