PHP mysqli_query()用法及代碼示例

定義和用法

這個mysqli_query()函數接受一個表示查詢的字符串值作為參數之一，並在數據庫上執行/執行給定的查詢。

用法

mysqli_query($con, query)

參數

Sr.No	參數及說明
1	con(Mandatory) 這是一個表示與 MySQL 服務器的連接的對象。
2	query(Mandatory) 這是一個字符串值，表示要執行的查詢。
3	mode(Optional) 這是一個表示結果模式的整數值。您可以將 MYSQLI_USE_RESULT 或 MYSQLI_STORE_RESULT 作為值傳遞給此參數。

返回值

對於 SELECT、SHOW、DESCRIBE 和 EXPLAIN 查詢，此函數返回一個 mysqli_result 對象，如果成功則保存查詢結果，如果失敗則返回 false。

對於其他查詢，此函數返回一個布爾值，如果操作/查詢成功，則為 true，否則為 false。

PHP版本

這個函數最初是在 PHP 版本 5 中引入的，適用於所有後續版本。

示例

以下示例演示了 mysqli_query() 函數的用法(程序風格) -

<?php
   $con = mysqli_connect("localhost", "root", "password", "mydb");

   mysqli_query($con, "CREATE TABLE IF NOT EXISTS my_team(ID INT, First_Name VARCHAR(255), Last_Name VARCHAR(255), Place_Of_Birth VARCHAR(255), Country VARCHAR(255))");
   print("Table Created ..."."\n");

   //Inserting a records into the my_team table
   mysqli_query($con, "insert into my_team values(1, 'Shikhar', 'Dhawan', 'Delhi', 'India')");
   mysqli_query($con, "insert into my_team values(2, 'Jonathan', 'Trott', 'CapeTown', 'SouthAfrica')");
   mysqli_query($con, "insert into my_team values(3, 'Kumara', 'Sangakkara', 'Matale', 'Srilanka')");
   mysqli_query($con, "insert into my_team values(4, 'Virat', 'Kohli', 'Delhi', 'India')");

   print("Records Inserted ..."."\n");
  
   //Closing the connection
   mysqli_close($con);
?>

這將產生以下結果 -

Table Created ...
Records Inserted ...

如果您觀察數據庫中表的內容，您可以看到插入的記錄，如下所示 -

mysql> select * from my_team;
+------+------------+------------+----------------+-------------+
| ID   | First_Name | Last_Name  | Place_Of_Birth | Country     |
+------+------------+------------+----------------+-------------+
|    1 | Shikhar    | Dhawan     | Delhi          | India       |
|    2 | Jonathan   | Trott      | CapeTown       | SouthAfrica |
|    3 | Kumara     | Sangakkara | Matale         | Srilanka    |
|    4 | Virat      | Kohli      | Delhi          | India       |
+------+------------+------------+----------------+-------------+
4 rows in set (0.00 sec)

示例

在麵向對象的風格中，這個函數的語法是 $con->query();以下是麵向對象樣式 $minus 中此函數的示例；

<?php
   $con = new mysqli("localhost", "root", "password", "mydb");

   //Inserting a records into the players table
   $con->query("CREATE TABLE IF NOT EXISTS players(First_Name VARCHAR(255), Last_Name VARCHAR(255), Country VARCHAR(255))");
   $con->query("insert into players values('Shikhar', 'Dhawan', 'India')");
   $con->query("insert into players values('Jonathan', 'Trott', 'SouthAfrica')");

   print("Data Created......");
   //Closing the connection
   $res = $con -> close();
?>

這將產生以下結果 -

Data Created......

如果您觀察數據庫中表的內容，您可以看到插入的記錄，如下所示 -

mysql> select * from players;
+------------+-----------+-------------+
| First_Name | Last_Name | Country     |
+------------+-----------+-------------+
| Shikhar    | Dhawan    | India       |
| Jonathan   | Trott     | SouthAfrica |
+------------+-----------+-------------+
2 rows in set (0.00 sec)

示例

以下示例打印 INSERT 和 SELECT 查詢的結果 -

<?php
   //Creating a connection
   $con = mysqli_connect("localhost", "root", "password", "mydb");

   mysqli_query($con, "CREATE TABLE IF NOT EXISTS my_team(ID INT, First_Name VARCHAR(255), Last_Name VARCHAR(255), Place_Of_Birth VARCHAR(255), Country VARCHAR(255))");
   print("Table Created ..."."\n");

   //Inserting a records into the my_team table
   $res = mysqli_query($con, "insert into my_team values(1, 'Shikhar', 'Dhawan', 'Delhi', 'India')");
   print("Result of Insert Query:".$res."\n");
   $res = mysqli_query($con, "insert into my_team values(2, 'Jonathan', 'Trott', 'CapeTown', 'SouthAfrica')");
   print("Result of Insert Query:".$res);

   $res = mysqli_query($con, "SELECT * FROM my_team");
   print("Result of the SELECT query:");
   print_r($res);

   //Closing the connection
   mysqli_close($con);
?>

這將產生以下結果 -

Table Created ...
Result of Insert Query:1
Result of Insert Query:1Result of the SELECT query:mysqli_result Object
(
    [current_field] => 0
    [field_count] => 5
    [lengths] =>
    [num_rows] => 2
    [type] => 0
)

示例

假設我們在數據庫中創建了一個表玩家並填充它，如下所示 -

CREATE TABLE Players (Name VARCHAR(255), Age INT, Score INT);
   insert into Players values('Dhavan', 33, 90),('Rohit', 28, 26),('Kohli', 25, 50);

以下示例從

mysqli_multi_query

函數 -

<?php
   //Creating a connection
   $con = mysqli_connect("localhost", "root", "password", "mydb");

   //Executing the multi query
   $query = "SELECT * FROM players";
 
   //Retrieving the records
   $res = mysqli_query($con, $query, MYSQLI_USE_RESULT);
   if ($res) {
      while ($row = mysqli_fetch_row($res)) {
         print("Name:".$row[0]."\n");
         print("Age:".$row[1]."\n");
      }
   }

   //Closing the connection
   mysqli_close($con);
?>

這將產生以下結果 -

Name:Dhavan
Age:33
Name:Rohit
Age:28
Name:Kohli
Age:25