Home Database Mysql Tutorial PHP操作MySQL的函数_MySQL

PHP操作MySQL的函数_MySQL

Jun 01, 2016 pm 02:05 PM
function operate result return connect

(1)mysql_connect(主机,用户名,口令);

返回一个连接号.

注意:mysql各用户的口令可以随该用户所在机器IP地址不同而改变.

另外,mSQL没有用户名机制,所以msql_connect只需要一个主机参数.

主机可以是IP地址或域名.



(2)mysql_create_db(数据库名);



(3)mysql_select_db(数据库名,连接号);

连接一个数据库.



(4)mysql_query(SQL语句,连接号);

如果SQL语句是select,则返回一个结果号.否则返回的值可以不理会.

如果失败,返回false.



(5)mysql_fetch_array(结果号);

取出下一行,返回一个数组.可以用数字下标访问(第一个字段是下标

0),也可以用字符串下标访问(即使用各字段名).

如已取了最后一行,返回false.



(6)mysql_fetch_field(结果号,[字段序号]);

如无字段序号,取下一个字段.

返回一个哈希表,下标有:

name,table,max_length,not_null,primary_key,unique_key,

multiple_key,numeric,blob,type,unsigned,zerofill

各下标的意思应该比较明白了.



(7)mysql_num_rows(结果号);mysql_num_fields(结果号);



(8)mysql_free_result(结果号);



(9)mysql_list_dbs();mysql_list_tables(数据库名);



(10)mysql_close(连接号);



(11)mysql_pconnect(主机,用户名,口令);



(12)mysql_select_db(数据库名,连接号);

连接一个数据库.



与mysql_connect完全相似,但建立一个"永久连接",该连接一经建立永不

关闭,即使使用mysql_close函数或程序执行完毕也不关闭.下一次试图建

立永久连接时,系统如发现已存在一个永久连接,则直接返回该连接号而

不重新创建.

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