sql中比较一个字符串中是否含有另一个字符串中的一个字符的实现代码,需要的朋友可以参考下。
版本一:按分隔符进行比较算法思路:按分隔符截取搜索字符串循环与待搜索字符进行比较
代码如下:
USE [Fly]
GO
--参数:@inStr 待搜索字串,@fndStr 搜索字串,@doc 分隔符
-- 例:select dbo.fSearch('1,2,3,4,5,6','3,6,5,8,2',',') 返回0-不匹配,返回1-匹配(@instr中有@fndStr内容)
--可以用于表搜索,如:
-- Select *,dbo.fSearch(str,'3,6,5,8,2',',') as 是否匹配 from 表名
-- @fndStr和@doc两个参数就需要你自己提供了,@inStr可以是数据表里的某个待搜索字段名
CREATE FUNCTION CGF_FN_Search(@inStr VARCHAR(500),@fndStr VARCHAR(500),@doc VARCHAR(5))
RETURNS INT
AS
BEGIN
DECLARE @i INT,@c VARCHAR(500),@fStr VARCHAR(500)
SET @fStr = @fndStr
WHILE(LEN(@fStr) > 0)
BEGIN
SET @i = Charindex(@doc, @fStr)
IF(@i = 0)
BEGIN
IF(CHARINDEX(@fStr,@inStr) > 0)
RETURN 1
ELSE
RETURN 0
END
ELSE
BEGIN
SET @c = SUBSTRING(@fStr,1,@i-1)
IF(CHARINDEX(@c,@inStr) > 0)
RETURN 1
ELSE
SET @fStr = SUBSTRING(@fStr,@i+LEN(@doc),LEN(@fStr))
END
END
RETURN 0
END
版本二:逐字进行比较
算法思路:逐字截取搜索字符串循环与待搜索字符进行比较
代码如下:
USE [Fly]
GO
/****** Object: UserDefinedFunction [dbo].[CGF_FN_SearchChar] Script Date: 09/03/2010 16:42:12 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE FUNCTION [dbo].[CGF_FN_SearchChar](@inStr VARCHAR(500),@fndStr VARCHAR(500))
RETURNS INT
AS
BEGIN
DECLARE @i INT,@f INT,@c VARCHAR(1)
SET @i = 1
SET @f = LEN(@fndStr)
WHILE(@i BEGIN
SET @c = SUBSTRING(@fndStr, @i, @i)
IF(CHARINDEX(@c,@inStr) > 0)
BEGIN
RETURN 1
END
SET @i = @i + 1
END
RETURN 0
END

MySQL is suitable for beginners to learn database skills. 1. Install MySQL server and client tools. 2. Understand basic SQL queries, such as SELECT. 3. Master data operations: create tables, insert, update, and delete data. 4. Learn advanced skills: subquery and window functions. 5. Debugging and optimization: Check syntax, use indexes, avoid SELECT*, and use LIMIT.

MySQL efficiently manages structured data through table structure and SQL query, and implements inter-table relationships through foreign keys. 1. Define the data format and type when creating a table. 2. Use foreign keys to establish relationships between tables. 3. Improve performance through indexing and query optimization. 4. Regularly backup and monitor databases to ensure data security and performance optimization.

MySQL is an open source relational database management system that is widely used in Web development. Its key features include: 1. Supports multiple storage engines, such as InnoDB and MyISAM, suitable for different scenarios; 2. Provides master-slave replication functions to facilitate load balancing and data backup; 3. Improve query efficiency through query optimization and index use.

SQL is used to interact with MySQL database to realize data addition, deletion, modification, inspection and database design. 1) SQL performs data operations through SELECT, INSERT, UPDATE, DELETE statements; 2) Use CREATE, ALTER, DROP statements for database design and management; 3) Complex queries and data analysis are implemented through SQL to improve business decision-making efficiency.

The basic operations of MySQL include creating databases, tables, and using SQL to perform CRUD operations on data. 1. Create a database: CREATEDATABASEmy_first_db; 2. Create a table: CREATETABLEbooks(idINTAUTO_INCREMENTPRIMARYKEY, titleVARCHAR(100)NOTNULL, authorVARCHAR(100)NOTNULL, published_yearINT); 3. Insert data: INSERTINTObooks(title, author, published_year)VA

The main role of MySQL in web applications is to store and manage data. 1.MySQL efficiently processes user information, product catalogs, transaction records and other data. 2. Through SQL query, developers can extract information from the database to generate dynamic content. 3.MySQL works based on the client-server model to ensure acceptable query speed.

The steps to build a MySQL database include: 1. Create a database and table, 2. Insert data, and 3. Conduct queries. First, use the CREATEDATABASE and CREATETABLE statements to create the database and table, then use the INSERTINTO statement to insert the data, and finally use the SELECT statement to query the data.

MySQL is suitable for beginners because it is easy to use and powerful. 1.MySQL is a relational database, and uses SQL for CRUD operations. 2. It is simple to install and requires the root user password to be configured. 3. Use INSERT, UPDATE, DELETE, and SELECT to perform data operations. 4. ORDERBY, WHERE and JOIN can be used for complex queries. 5. Debugging requires checking the syntax and use EXPLAIN to analyze the query. 6. Optimization suggestions include using indexes, choosing the right data type and good programming habits.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Atom editor mac version download
The most popular open source editor

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

Dreamweaver CS6
Visual web development tools