PHP的MySQL常用函数的解决办法
内容摘要
这篇文章主要为大家详细介绍了PHP的MySQL常用函数的简单示例,具有一定的参考价值,可以用来参考一下。
对此感兴趣的朋友,看看idc笔记做的技术笔记!1、mysql_connect()-建立数据
对此感兴趣的朋友,看看idc笔记做的技术笔记!1、mysql_connect()-建立数据
文章正文
这篇文章主要为大家详细介绍了PHP的MySQL常用函数的简单示例,具有一定的参考价值,可以用来参考一下。
对此感兴趣的朋友,看看idc笔记做的技术笔记!
1、mysql_connect()-建立数据库连接格式:resource mysql_connect([string hostname [:port] [:/path/to/socket] [, string username] [, string password]])例:$conn = @mysql_connect("localhost", "username", "password") or die("不能连接到Mysql Server");说明:使用该连接必须显示的关闭连接2、mysql_pconnect()-建立数据库连接 格式:resource mysql_pconnect([string hostname [:port] [:/path/to/socket] [, string username] [, string password]])例:$conn = @mysql_pconnect("localhost", "username", "password") or dir("不能连接到Mysql Server");说明:使用该连接函数不需要显示的关闭连接,它相当于使用了连接池3、mysql_close()-关闭数据库连接例:$conn = @mysql_connect("localhost", "username", "password") or die("不能连接到Mysql Server");@mysql_select_db("MyDatabase") or die("不能选择这个数据库,或数据库不存在");echo "你已经连接到MyDatabase数据库";mysql_close();4、mysql_select_db()-选择数据库格式:boolean mysql_select_db(string db_name [, resource link_id])例:$conn = @mysql_connect("localhost", "username", "password") or die("不能连接到Mysql Server");@mysql_select_db("MyDatabase") or die("不能选择这个数据库,或数据库不存在");5、mysql_query()-查询MySQL格式:resource mysql_query (string query, [resource link_id])例:$linkId = @mysql_connect("localhost", "username", "password") or die("不能连接到Mysql Server");@mysql_select_db("MyDatabase") or die("不能选择这个数据库,或者数据库不存在");$query = "select * from MyTable";$result = mysql_query($query);mysql_close();说明:若SQL查询执行成功,则返回资源标识符,失败时返回FALSE。若执行更新成功,则返回TRUE,否则返回FALSE6、mysql_db_query()-查询MySQL 格式:resource mysql_db_query(string database, string query [, resource link_id])例:$linkId = @mysql_connect("localhost", "username", "password") or die("不能连接到MysqlServer");$query = "select * from MyTable";$result = mysql_db_query("MyDatabase", $query);mysql_close();说明:为了使代码清晰,不推荐使用这个函数调用7、mysql_result()-获取和显示数据格式:mixed mysql_result (resource result_set, int row [, mixed field])例:$query = "select id, name from MyTable order by name";$result = mysql_query($query);for($count=0;$count<=mysql_numrows($result);$count++){$c_id = mysql_result($result, 0, "id");$c_name = mysql_result($result, 0, "name");echo $c_id,$c_name;}说明:最简单、也是效率最低的数据获取函数8、mysql_fetch_row()-获取和显示数据格式:array mysql_fetch_row (resource result_set)例:$query = "select id, name from MyTable order by name";$result = mysql_query($query);while (list($id, $name) = mysql_fetch_row($result)) {echo("Name: $name ($id) <br />");}说明:函数从result_set中获取整个数据行,将值放在一个索引数组中。通常会结使list()函数使用9、mysql_fetch_array()-获取和显示数据 格式:array mysql_fetch_array (resource result_set [, int result_type])例:$query = "select id, name from MyTable order by name";$result = mysql_query($query);while($row = mysql_fetch_array($result, MYSQL_ASSOC)) {$id = $row["id"];$name = $row["name"];echo "Name: $name ($id) <br />";}又例:$query = "select id, name from MyTable order by name";$result = mysql_query($query);while($row = mysql_fetch_array($result, MYSQL_NUM)) {$id = $row[0];$name = $row[1];echo "Name: $name ($id) <br />";}说明:result_type的值有:MYSQL_ASSOC: 字段名表示键,字段内容为值MYSQL_NUM: 数值索引数组,操作与mysql_fetch_ros()函数一样MYSQL_BOTH: 即作为关联数组又作为数值索引数组返回。result_type的默认值。10、mysql_fetch_assoc()-获取和显示数据格式:array mysql_fetch_assoc (resource result_set)相当于调用 mysql_fetch_array(resource, MYSQL_ASSOC);11、mysql_fetch_object()-获取和显示数据 格式:object mysql_fetch_object(resource result_set)例:$query = "select id, name from MyTable order by name";while ($row = mysql_fetch_object($result)) {$id = $row->id;$name = $row->name;echo "Name: $name ($id) <br />";}说明:返回一个对象,在操作上与mysql_fetch_array()相同12、mysql_num_rows()-所选择的记录的个数格式:int mysql_num_rows(resource result_set)例:query = "select id, name from MyTable where id > 65";$result = mysql_query($query);echo "有".mysql_num_rows($result)."条记录的ID大于65";说明:只在确定select查询所获取的记录数时才有用。13、mysql_affected_rows()-受Insert,update,delete影响的记录的个数格式:int mysql_affected_rows([resource link_id])例:$query = "update MyTable set name='CheneyFu' where id>=5";$result = mysql_query($query);echo "ID大于等于5的名称被更新了的记录数:".mysql_affected_rows();说明:该函数获取受INSERT,UPDATE或DELETE更新语句影响的行数14、mysql_list_dbs()-获取数据库列表信息格式:resource mysql_list_dbs([resource link_id])例:mysql_connect("localhost", "username", "password");$dbs = mysql_list_dbs();echo "Databases: <br />";while (list($db) = mysql_fetch_rows($dbs)) {echo "$db <br />";}说明:显示所有数据库名称15、mysql_db_name()-获取数据库名 格式:string mysql_db_name(resource result_set, integer index)说明:该函数获取在mysql_list_dbs()所返回result_set中位于指定index索引的数据库名16、mysql_list_tables()-获取数据库表列表格式:resource mysql_list_tables(string database [, resource link_id])例:mysql_connect("localhost", "username", "password");$tables = mysql_list_tables("MyDatabase");while (list($table) = mysql_fetch_row($tables)) {echo "$table <br />";}说明:该函数获取database中所有表的表名17、mysql_tablename()-获取某个数据库表名格式:string mysql_tablename(resource result_set, integer index)例:mysql_connect("localhost", "username", "password");$tables = mysql_list_tables("MyDatabase");$count = -1;while (++$count < mysql_numrows($tables)) {echo mysql_tablename($tables, $count)."<br />";}说明:该函数获取mysql_list_tables()所返回result_set中位于指定index索引的表名18、mysql_fetch_field()-获取字段信息 格式:object mysql_fetch_field(resource result [, int field_offset])例:mysql_connect("localhost", "username", "password");mysql_select_db("MyDatabase");$query = "select * from MyTable";$result = mysql_query($query);$counts = mysql_num_fields($result);for($count = 0; $count < $counts; $count++) {$field = mysql_fetch_field($result, $count);echo "<p>$field->name $field->type ($field->max_length) </p>";}说明:返回的对象共有12个对象属性:name: 字段名table: 字段所在的表max_length:字段的最大长度not_null: 如果字段不能为null,则为1,否则0primary_key: 如果字段为主键,则为1,否则0unique_key: 如果字段是唯一键,则为1, 否则0multiple_key: 如果字段为非唯一,则为1,否则0numeric: 如果字段为数值则为1,否则0blob: 如果字段为BLOB则为1,否则为0type: 字段的数据类型unsigned: 如果字段为无符号数则为1,否则为0zerofill: 如果字段为“零填充”则为1, 否则为019、mysql_num_fields()-获取查询的字段个数格式:integer mysql_num_fields(resource result_set)例:$query = "select id,name from MyTable order by name";$result = mysql_query($query);echo "这个查询的字段数是:".mysql_num_fields($result)."<br />";20、mysql_list_fields()-获取指定表的所有字段的字段名 格式:resource mysql_list_fields (string database_name, string table_name [, resource link_id])例:$fields =mysql_list_fields("MyDatabase", "MyTable");echo "数据库MyDatabase中表MyTable的字段数: ".mysql_num_fields($fields)."<br />";21、mysql_field_flags()-获取指定的字段选项 格式:string mysql_field_flags (resource result_set, integer field_offset)例:$query = "select id, name from MyTable order by name";$result = mysql_query($query);$row=mysql_fetch_wor($row);22、mysql_field_len()-获取指定的字段的最大长度格式:integer mysql_field_len (resource result_set, integer field_offset)例:$query = "select name from MyTable";$result = mysql_query($query);$row = mysql_fetch_row($result);echo mysql_field_len($result, 0)."<br />";说明:如果mysql_field_len($reseult, 0) = 16777215那么numer_format(mysql_field_len($result))等于16,777,21523、mysql_field_name()-获取字段名格式:string mysql_field_name (resource result_set, int field_offset)例:$query = "select id as PKID, name from MyTable order by name";$result = mysql_query($query);$row = mysql_fetch_row($result);echo mysql_field_name($result, 0); // Result: PKID24、mysql_field_type()-获取字段类型 格式:string mysql_field_type (resource result_set, int field_offset)例:$query = "select id, name from MyTable order by name";$result = mysql_query($query);$row = mysql_fetch_row($result);echo mysql_field_type($result, 0); // Result: int25、mysql_field_table()-获取字段所在表名格式:string mysql_field_table (resource result_set, int field_offset)例:$query = "select id as PKID, name from MyTable order by name";$result = mysql_query($query);$row = mysql_fetch_row($result);echo mysql_field_table($result, 0); // Result: MyTable注:关于PHP的MySQL常用函数的简单示例的内容就先介绍到这里,更多相关文章的可以留意
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