Summary of definition and usage of data access functions

一、数据库连接池开发的时候经常会需要对数据库进行一些操作，比如说常见的增删改查之类的，当数据量小的时候，可以直接进行操作，但是当数据量增多的时候，每一次连接以及释放数据库都会耗费一定的时间，这个时候，可以采用数据库连接池来保持数据库的链接，减少连接数据库对程序带来的开销，并且可以减少数据库的压力，那么数据库链接池是一个什么样的东西呢？顾名思义，它是一个池子，池子里放的是对数据库的链接，打个比方鱼塘，就是养鱼的池子，想要吃鱼可以直接去捞，不用自己去亲自的买鱼苗养鱼等，数据库连接池就是放的对于数据库的链接，统一的把所有的链接都给建立好了，用的时候就可以直接的从里面去取，用完了之后放回池子里就可以，既然用这个东西，那么我们也没必要完全自己去写代码实现，有些开源的可以直接用，常见的有三种开源的连接池，c3p0，dbcp，proxool这三种，对于c3p0、proxool这两种没用过，只是简单的用过

1. 连接池配置的10篇内容推荐

简介：一、数据库连接池开发的时候经常会需要对数据库进行一些操作，比如说常见的增删改查之类的，当数据量小的时候，可以直接进行操作，但是当数据量增多的时候，每一次连接以及释放数据库都会耗费一定的时间，这个时候，可以采用数据库连接池来保持数据库的链接，减少连接数据库对程序带来的开销，并且可以减少数据库的压力，那么数据库链接池是一个什么样的东西呢？顾名思义，它是一个池子，池子里放的是对数据库的链接，打个比方鱼塘...

2. prepare的10篇内容推荐

简介：mysqli相对于mysql有很多优势，建议大家使用，如果没有了解，可以查看mysql的基础教程：mysqli连接数据库 和 mysqli预处理prepare使用 。不仅如此，mysqli更是支持多查询特性，看下面这段php代码：

3. 关于mysql_select_db()函数的文章推荐

简介：PHP操作MySQL数据库的方法-如何选择数据库文件在我们日常PHP开发工作中，当我们把要从数据库获取数据的时候， 在PHP连接数据库后，接下来就是我们要选择数据库文件，就要使用到一个函数，mysql_select_db()函数选择数据库！在选择数据库之前，我们首先做的就是PHP与数据库的连接，这个我们在上一篇文章《使用mysql_connect()函数连接数据库（PHP操作MySQL数据库的方法...

4. 有关mysql_select_db()的文章推荐

简介：PHP操作MySQL数据库的方法-如何选择数据库文件在我们日常PHP开发工作中，当我们把要从数据库获取数据的时候， 在PHP连接数据库后，接下来就是我们要选择数据库文件，就要使用到一个函数，mysql_select_db()函数选择数据库！在选择数据库之前，我们首先做的就是PHP与数据库的连接，这个我们在上一篇文章《使用mysql_connect()函数连接数据库（PHP操作MySQL数据库的方法...

5. 关于SSE的10篇文章推荐

Introduction: PHP can connect to the database but cannot create database, how to solve it? First post the code: PHP code, I wrote this code under zend, the running environment is WAMP, the running result is successERROR, which means there is no problem connecting to the database, but there is an error when executing CREATE DATABASE hello. I don't understand what's going on, please give me some advice. ------Solution--------------------See if you have permission to create a database...

6. mysql_fetch_field function instance usage summary

##Introduction: mysql_init initializes the database link-gets a link mysql_real_connect connects to the database server to execute the mysql_query query – the query statement is a string that retrieves each row separately mysql_store_result – the results are stored in the link, which is a one-time query. From the result set, the header information is obtained – mysql_fetch_fields – the header information is stored in the MYSQL_FIELD type The memory space parsed table header pointed to by the pointer –mysql_...

7. Summary of usage of mysql_fetch_field() function

Introduction: mysql_init initializes the database link – gets a link mysql_real_connect connects to the database server and executes the mysql_query query – the query statement is a string to retrieve each row separately mysql_store_result – The results are stored in the link and belong to a one-time query. From the result set, get the header information – mysql_fetch_fields – the header information is stored in the memory space pointed to by the MYSQL_FIELD type pointer. Parse the header – mysql_...

8. 10 recommended articles about mysql_fetch_assoc()

##Introduction: mysql_connect() connects to the database mysql_select_db selects the database mysql_fetch_assoc() gets the result set mysql_query() executes the sql statement example as follows:

9.

5 recommended articles about mysql_errno()

Introduction: PHP can connect to the database but cannot create database, how to solve it? First post the code: PHP code, I wrote this code under zend, the running environment is WAMP, the running result is successERROR, which means there is no problem connecting to the database, but there is an error when executing CREATE DATABASE hello. I don't understand what's going on, please give me some advice. ------Solution--------------------See if you have permission to create a database...

10.

Recommended 10 articles about the mysql_errno() function

##Introduction: PHP can connect Database but cannot create database, how to solve it? First post the code: PHP code, I wrote this code under zend, the running environment is WAMP, the running result is successERROR, which means there is no problem connecting to the database, but there is an error when executing CREATE DATABASE hello. I don't understand what's going on, please give me some advice. ------Solution--------------------Check if you have permission to create a database-----...

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