最近一直在研究PHP與MYSQL,感覺PHP與MYSQL交互的函數都是過程化的,當然也有mysqli擴展,面向對象,Java和C#寫多了之後,再寫PHP,有些不適應,感覺又回到了學C的年代。今天學習了一些函數,記錄下來,以便日後忘記時,可以參考。
說 明 函 數 名 函 數 詳 細 函 數 說 明 建立數據庫連接 mysql_connect() resource mysql_connect([string hostname [:port] [:/path/to/socket] [, string username] [, string password]])
示例:$conn = @mysql_connect("localhost", "username", "password") or dir("不能連接到Mysql Server");
使用該連接必須顯示的關閉連接 建立數據庫連接 mysql_pconnect() resource mysql_pconnect([string hostname [:port] [:/path/to/socket] [, string username] [, string password]])示例:$conn = @mysql_pconnect("localhost", "username", "password") or dir("不能連接到Mysql Server");
使用該連接函數不需要顯示的關閉連接,它相當於使用了連接池 關閉數據庫連接 mysql_close() $conn = @mysql_connect("localhost", "username", "password") or die("不能連接到Mysql Server");@mysql_select_db("MyDatabase") or die("不能選擇這個數據庫,或數據庫不存在");
echo "你已經連接到MyDatabase數據庫";
mysql_close();
選擇數據庫 mysql_select_db() boolean mysql_select_db(string db_name [, resource link_id])$conn = @mysql_connect("localhost", "username", "password") or die("不能連接到Mysql Server");
@mysql_select_db("MyDatabase") or die("不能選擇這個數據庫,或數據庫不存在");
查詢MySQL mysql_query() resource mysql_query (string query, [resource link_id])$linkId = @mysql_connect("localhost", "username", "password") or die("不能連接到Mysql Server");
@mysql_select_db("MyDatabase") or die("不能選擇這個數據庫,或者數據庫不存在");
$query = "select * from MyTable";
$result = mysql_query($query);
mysql_close();
若SQL查詢執行成功,則返回資源標識符,失敗時返回FALSE。若執行更新成功,則返回TRUE,否則返回FALSE 查詢MySQL mysql_db_query() resource mysql_db_query(string database, string query [, resource link_id])$linkId = @mysql_connect("localhost", "username", "password") or die("不能連接到MysqlServer");
$query = "select * from MyTable";
$result = mysql_db_query("MyDatabase", $query);
mysql_close();
為了使代碼清晰,不推薦使用這個函數調用 獲取和顯示數據 mysql_result() mixed mysql_result (resource result_set, int row [, mixed field])$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");
最簡單、也是效率最低的數據獲取函數 獲取和顯示數據 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 />");
}
函數從result_set中獲取整個數據行,將值放在一個索引數組中。通常會結使list()函數使用 獲取和顯示數據 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: 字段名表示鍵,字段內容為值
MYSQL_NUM: 數值索引數組,操作與mysql_fetch_ros()函數一樣
MYSQL_BOTH: 即作為關聯數組又作為數值索引數組返回。result_type的默認值。
獲取和顯示數據 mysql_fetch_assoc() array mysql_fetch_assoc (resource result_set)相當於調用 mysql_fetch_array(resource, MYSQL_ASSOC);
獲取和顯示數據 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 />";
}
在操作上與mysql_fetch_array()相同 所選擇的記錄 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($result)."條記錄的ID大於65";
只在確定select查詢所獲取的記錄數時才有用。 受影響的記錄 mysql_affected_rows() int mysql_affected_rows([resource link_id])$query = "update MyTable set name='CheneyFu' where id>=5";
$result = mysql_query($query);
echo "ID大於等於5的名稱被更新了的記錄數:".mysql_affected_rows();
該函數獲取受INSERT,UPDATE或DELETE更新語句影響的行數 獲取數據庫列表信息 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 />";
}
獲取數據庫名 mysql_db_name() string mysql_db_name(resource result_set, integer index) 該函數獲取在mysql_list_dbs()所返回result_set中位於指定index索引的數據庫名 獲取數據庫表列表 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 />";
}
該函數獲取database中所有表的表名 獲取數據庫表名 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 />";
}
該函數獲取mysql_list_tables()所返回result_set中位於指定index索引的表名 獲取字段信息 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>";
}
返回的對象共有12個對象屬性:name: 字段名
table: 字段所在的表
max_length: 字段的最大長度
not_null: 如果字段不能為null,則為1,否則0
primary_key: 如果字段為主鍵,則為1,否則0
unique_key: 如果字段是唯一鍵,則為1, 否則0
multiple_key: 如果字段為非唯一,則為1,否則0
numeric: 如果字段為數值則為1,否則0
blob: 如果字段為BLOB則為1,否則為0
type: 字段的數據類型
unsigned: 如果字段為無符號數則為1,否則為0
zerofill: 如果字段為“零填充”則為1, 否則為0
獲取查詢的字段數 mysql_num_fields() integer mysql_num_fields (resource result_set)$query = "select id, name from MyTable order by name";
$result = mysql_query($query);
echo "這個查詢的字段數是:".mysql_num_fields($result)."<br />";
返回查詢result_set中的字段數 獲取指定表的所有字段的字段名 mysql_list_fields() resource mysql_list_fields (string database_name, string table_name [, resource link_id])$fields = mysql_list_fields("MyDatabase", "MyTable");
echo "數據庫MyDatabase中表MyTable的字段數: ".mysql_num_fields($fields)."<br />";
獲取指定的字段選項 mysql_field_flags() string mysql_field_flags (resource result_set, integer field_offset) 獲取指定的字段的最大長度 mysql_field_len() integer mysql_field_len (resource result_set, integer field_offset)$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那麼numer_format(mysql_field_len($result))等於16,777,215
獲取字段名 mysql_field_name() string mysql_field_name (resource result_set, int field_offset)$query = "select id as PKID, name from MyTable order by name";
$result = mysql_query($query);
$row = mysql_fetch_row($result);
echo mysql_field_name($result, 0); // Result: PKID
獲取字段類型 mysql_field_type() string mysql_field_type (resource result_set, int field_offset)$query = "select id, name from MyTable order by name";
$result = mysql_query($query);
$row = mysql_fetch_row($result);
echo mysql_field_type($result, 0); // Result: int
獲取字段所在表名 mysql_field_table() string mysql_field_table (resource result_set, int field_offset)$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); //