PHP与MYSQL交互函数表学习笔记
说 明函 数 名函 数 详 细函 数 说 明建立数据库连接mysql_connect()resource mysql_connect([string hostname [:port] [:/path/to/socket] [, string username] [, string password]])示例：$conn = @mysql_connect('localhost', 'username', 'password') or dir('不能连接到Mysql Server');使用该连接必须显示的关闭连接建立数据库连接mysql_pconnect()resource mysql_pconnect([string hostname [:port] [:/path/to/socket] [, string username] [, string password]])示例：$conn = @mysql_pconnect('localhost', 'username', 'password') or dir('不能连接到Mysql Server');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关闭数据库连接mysql_close()$conn = @mysql_connect('localhost', 'username', 'password') or die('不能连接到Mysql Server');@mysql_select_db('MyDatabase') or die('不能选择这个数据库，或数据库不存在');echo '你已经连接到MyDatabase数据库';mysql_close() 选择数据库mysql_select_db()boolean mysql_select_db(string db_name [, resource link_id])$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'); 查询MySQLmysql_query()resource mysql_query (string query, [resource link_id])$linkId = @mysql_connect('localhost', 'username', 'password') or die('不能连接到Mysql Server');@mysql_select_db('MyDatabase') or die('不能选择这个数据库，或者数据库不存在');$query = 'select * from MyTable';$result = mysql_query($query);mysql_close();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FALSE查询MySQLmysql_db_query()resource mysql_db_query(string database, string query [, resource link_id])$linkId = @mysql_connect('localhost', 'username', 'password') or die('不能连接到MysqlServer');$query = 'select * from MyTable';$result = mysql_db_query('MyDatabase', $query);mysql_close();为了使代码清晰，不推荐使用这个函数调用获取和显示数据mysql_result()mixed mysql_result (resource result_set, int row [, mixed field])$query = 'select id, name from MyTable order by name';$result = mysql_query($query);$c_id = mysql_result($result, 0, 'id');$c_name = mysql_result($result, 0, 'name');最简单、也是效率最低的数据获取函数获取和显示数据mysql_fetch_row()array mysql_fetch_row (resource result_set)$query = 'select id, name from MyTable order by name';$result = mysql_query($query);while (list($id, $name) = mysql_fetch_row($result)) { echo('Name: $name ($id) <br />');}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()函数使用获取和显示数据mysql_fetch_array()array mysql_fetch_array (resource result_set [, int result_type])$query = 'select id, name from MyTable order by name';$result = mysql_query($query);while($row = mysql_fetch_array($result, MYSQL_ASSOC)) { $id = $row['id']; $name = $row['name']; echo 'Name: $name ($id) <br />';}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。获取和显示数据mysql_fetch_assoc()array mysql_fetch_assoc (resource result_set)相当于调用 mysql_fetch_array(resource, MYSQL_ASSOC); 获取和显示数据mysql_fetch_object()object mysql_fetch_object(resource result_set)$query = 'select id, name from MyTable order by name';while ($row = mysql_fetch_object($result)) { $id = $row->id; $name = $row->name; echo 'Name: $name ($id) <br />';}在操作上与mysql_fetch_array()相同所选择的记录mysql_num_rows()int mysql_num_rows(resource result_set)#query = 'select id, name from MyTable where id > 65';$result = mysql_query($query);echo '有'.mysql_num_rows($result).'条记录的ID大于65';只在确定select查询所获取的记录数时才有用。受影响的记录mysql_affected_rows()int mysql_affected_rows([resource link_id])$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();该函数获取受INSERT,UPDATE或DELETE更新语句影响的行数获取数据库列表信息mysql_list_dbs()resource mysql_list_dbs([resource link_id])mysql_connect('localhost', 'username', 'password');$dbs = mysql_list_dbs();echo 'Databases: <br />';while (list($db) = mysql_fetch_rows($dbs)) { echo '$db <br />';} 获取数据库名mysql_db_name()string mysql_db_name(resource result_set, integer index)该函数获取在mysql_list_dbs()所返回result_set中位于指定index索引的数据库名获取数据库表列表mysql_list_tables()resource mysql_list_tables(string database [, resource link_id])mysql_connect('localhost', 'username', 'password');$tables = mysql_list_tables('MyDatabase');while (list($table) = mysql_fetch_row($tables)) { echo '$table <br />';}该函数获取database中所有表的表名获取数据库表名mysql_tablename()string mysql_tablename(resource result_set, integer index)mysql_connect('localhost', 'username', 'password');$tables = mysql_list_tables('MyDatabase');$count = -1;while (++$count < mysql_numrows($tables)) { echo mysql_tablename($tables, $count).'<br />';}该函数获取mysql_list_tables()所返回result_set中位于指定index索引的表名获取字段信息mysql_fetch_field()object mysql_fetch_field(resource result [, int field_offset])mysql_connect('localhost', 'username', 'password');mysql_select_db('MyDatabase');$query = 'select * from MyTable';$result = mysql_query($query);$fields = mysql_num_fields($result);for($count = 0; $count < $fieds; $count++) { $field = mysql_fetch_field($result, $count); echo '<p>$field->name $field->type ($field->max_length) </p>';}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0获取查询的字段数mysql_num_fields()integer mysql_num_fields (resource result_set)$query = 'select id, name from MyTable order by name';$result = mysql_query($query);echo '这个查询的字段数是：'.mysql_num_fields($result).'<br />';返回查询result_set中的字段数获取指定表的所有字段的字段名mysql_list_fields()resource mysql_list_fields (string database_name, string table_name [, resource link_id])$fields = mysql_list_fields('MyDatabase', 'MyTable');echo '数据库MyDatabase中表MyTable的字段数： '.mysql_num_fields($fields).'<br />'; 获取指定的字段选项mysql_field_flags()string mysql_field_flags (resource result_set, integer field_offset) 获取指定的字段的最大长度mysql_field_len()integer mysql_field_len (resource result_set, integer field_offset)$query = 'select name from MyTable';$result = mysql_query($query);$row = mysql_fetch_row($result);echo mysql_field_len($result, 0).'<br />';如果mysql_field_len($reseult, 0) = 16777215那么numer_format(mysql_field_len($result))等于16,777,215获取字段名mysql_field_name()string mysql_field_name (resource result_set, int field_offset)$query = 'select id as PKID, name from MyTable order by name';$result = mysql_query($query);$row = mysql_fetch_row($result);echo mysql_field_name($result, 0); // Result: PKID 获取字段类型mysql_field_type()string mysql_field_type (resource result_set, int field_offset)$query = 'select id, name from MyTable order by name';$result = mysql_query($query);$row = mysql_fetch_row($result);echo mysql_field_type($result, 0); // Result: int 获取字段所在表名mysql_field_table()string mysql_field_table (resource result_set, int field_offset)$query = 'select id as PKID, name from MyTable order by name';$result = mysql_query($query);$row = mysql_fetch_row($result);echo mysql_field_table($result, 0); // Result: MyTable
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