PHP connecting to MySQL database

Petr Faltus development

Example source code in PHP how to connect to the MySQL database, how to update rows, how to read the table and how to call the storage function and the storage procedure.

mysql-client.php

GitHub repository: mysql-connection-source-codes

git clone https://github.com/petrfaltus/mysql-connection-source-codes.git

Directories to mysql-client.php in the repository: php

<?php

/*
2) In the php.ini added lines:
[PHP]
extension_dir = "ext"
extension=pdo_mysql
[Date]
date.timezone = Europe/Prague

*/

$db_driver = "mysql";

$db_host = "localhost";
$db_port = 3306;
$db_name = "testdb";
$db_username = "testuser";
$db_password = "T3stUs3r!";
$db_table = "people";

$db_update_column = "remark";
$db_update_column_variable = ":updatevar";

$db_column = "id";
$db_column_variable = ":var";
$db_column_value = 1;

$db_factorial_variable = ":n";
$db_factorial_value = 4;

$db_add_and_subtract_a_variable = ":a";
$db_add_and_subtract_a_value = 12;
$db_add_and_subtract_b_variable = ":b";
$db_add_and_subtract_b_value = 5;

$db_add_and_subtract_x_env_variable = "@env_var_x";
$db_add_and_subtract_y_env_variable = "@env_var_y";

$availableDrivers = PDO::getAvailableDrivers();

echo "Available PDO drivers ";
print_r($availableDrivers);
echo PHP_EOL;

if (!in_array($db_driver, $availableDrivers))
  {
   echo "PDO driver ".$db_driver." or it's subdriver is not available or has not been enabled in php.ini".PHP_EOL;
   exit;
  }

try
  {
   // Build the connection string and connect the database
   $dsn = $db_driver.":host=".$db_host.":".$db_port.";dbname=".$db_name;
   $conn = new PDO($dsn, $db_username, $db_password);

   echo "ATTR_CLIENT_VERSION = ".$conn->getAttribute(PDO::ATTR_CLIENT_VERSION).PHP_EOL;
   echo "ATTR_CONNECTION_STATUS = ".$conn->getAttribute(PDO::ATTR_CONNECTION_STATUS).PHP_EOL;
   echo "ATTR_DRIVER_NAME = ".$conn->getAttribute(PDO::ATTR_DRIVER_NAME).PHP_EOL;
   echo "ATTR_SERVER_INFO = ".$conn->getAttribute(PDO::ATTR_SERVER_INFO).PHP_EOL;
   echo "ATTR_SERVER_VERSION = ".$conn->getAttribute(PDO::ATTR_SERVER_VERSION).PHP_EOL;
   echo PHP_EOL;

   // UPDATE statement
   $new_comment = "PHP ".date("j.n.Y H:i:s");

   $stm0query = "update ".$db_table." set ".$db_update_column."=".$db_update_column_variable." where ".$db_column."!=".$db_column_variable;
   echo $stm0query.PHP_EOL;

   $stm0 = $conn->prepare($stm0query);
   $stm0->bindParam($db_update_column_variable, $new_comment, PDO::PARAM_STR);
   $stm0->bindParam($db_column_variable, $db_column_value, PDO::PARAM_INT);
   $stm0->execute();
   echo "Total updated rows: ".$stm0->rowCount().PHP_EOL;
   echo PHP_EOL;

   $stm0 = null;

   // Full SELECT statement
   $stm1query = "select * from ".$db_table;
   echo $stm1query.PHP_EOL;

   $stm1 = $conn->prepare($stm1query);
   $stm1->execute();
   echo "Total columns x rows: ".$stm1->columnCount()." x ".$stm1->rowCount().PHP_EOL;

   echo "Fetch all rows ";
   $lines1 = $stm1->fetchAll(PDO::FETCH_ASSOC);
   if ($lines1 == false)
     print_r($stm1->errorInfo());
   else
     print_r($lines1);
   echo PHP_EOL;

   $stm1 = null;

   // SELECT WHERE statement
   $stm2query = "select count(*) from ".$db_table." where ".$db_column."!=".$db_column_variable;
   echo $stm2query.PHP_EOL;

   $stm2 = $conn->prepare($stm2query);
   $stm2->bindParam($db_column_variable, $db_column_value, PDO::PARAM_INT);
   $stm2->execute();
   echo "Total columns x rows: ".$stm2->columnCount()." x ".$stm2->rowCount().PHP_EOL;

   echo "Fetch all rows ";
   $lines2 = $stm2->fetchAll(PDO::FETCH_ASSOC);
   if ($lines2 == false)
     print_r($stm2->errorInfo());
   else
     print_r($lines2);
   echo PHP_EOL;

   $stm2 = null;

   // SELECT function statement
   $stm3query = "select factorial(".$db_factorial_variable.")";
   echo $stm3query.PHP_EOL;

   $stm3 = $conn->prepare($stm3query);
   $stm3->bindParam($db_factorial_variable, $db_factorial_value, PDO::PARAM_INT);
   $stm3->execute();
   echo "Total columns: ".$stm3->columnCount().PHP_EOL;

   echo "Fetch all rows ";
   $lines3 = $stm3->fetchAll(PDO::FETCH_ASSOC);
   if ($lines3 == false)
     print_r($stm3->errorInfo());
   else
     print_r($lines3);
   echo PHP_EOL;

   $stm3 = null;

   // CALL procedure statement
   $stm4query = "call add_and_subtract(".$db_add_and_subtract_a_variable.", ".$db_add_and_subtract_b_variable.", ".$db_add_and_subtract_x_env_variable.", ".$db_add_and_subtract_y_env_variable.")";
   echo $stm4query.PHP_EOL;

   $stm4 = $conn->prepare($stm4query);
   $stm4->bindParam($db_add_and_subtract_a_variable, $db_add_and_subtract_a_value, PDO::PARAM_INT);
   $stm4->bindParam($db_add_and_subtract_b_variable, $db_add_and_subtract_b_value, PDO::PARAM_INT);
   $stm4->execute();

   $stm4error = $stm4->errorInfo();
   if ((isset($stm4error[0])) and ($stm4error[0] === "00000"))
     {
      $stm4bQuery = "select ".$db_add_and_subtract_x_env_variable.", ".$db_add_and_subtract_y_env_variable;
      echo $stm4bQuery.PHP_EOL;

      $stm4b = $conn->prepare($stm4bQuery);
      $stm4b->execute();
      echo "Total columns: ".$stm4b->columnCount().PHP_EOL;

      echo "Fetch all rows ";
      $lines4b = $stm4b->fetchAll(PDO::FETCH_ASSOC);
      if ($lines4b == false)
        print_r($stm4b->errorInfo());
      else
        print_r($lines4b);
      echo PHP_EOL;
     }
   else
     print_r($stm4error);

   $stm4 = null;

   // Disconnect the database
   $conn = null;
  }
catch (PDOException $e)
  {
   echo $e->getMessage().PHP_EOL;
  }

?>

Previous example

All examples

Following example

🤝 Your IP address is 3.238.98.39

💻💽💾 Useful examples and tools for home and professional programming.