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Falah Al Fitri
Falah Al Fitri

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PHP and MySQL 30: query select

#php #mysql #mysqli #pdo

Happy Coding

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In this post, we will learn about how to use query SELECT in PHP for retrieve data from database MySQL, with 3 ways:

  1. MySQLi procedural
  2. MySQLi object-oriented
  3. PDO

For known, how to connect to database, can be learned in here

Insert query is used for insert data or record into database

Syntax:

 SELECT column1, column2, column3 FROM table_name;
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using wilcard (*) for select all column

 SELECT * FROM table_name;
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Example:

 $sql = "SELECT id, firstname, lastname "; $sql .= "FROM users " ;
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 $sql = "SELECT * "; $sql .= "FROM users " ;
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And, for execute the query, we will use 3 ways:

1. MySQLi1 procedural

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Execute query using mysqli::query2 and get a $result:

 $result = mysqli_query( $connection, $sql );
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Display data using mysqli_result::fetch_assoc3, alternative using mysqli_result::fetch_object4:

 echo "<pre>"; echo "No \t"; echo "ID \t"; echo "Firstname \t\t"; echo "Lastname \n"; $no = 1; /* variabel $no */ /* loop while */ while ( $row = mysqli_fetch_assoc($result) ) { echo $no . "\t"; echo $row['id'] . "\t"; echo $row['firstname'] . "\t\t"; echo $row['lastname'] . "\n"; $no++; /* increment */ } echo "</pre>";
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Close connection using mysqli::close5:

 mysqli_close($connection);
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Source Code:

2. MySQLi1 object-oriented

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Execute query using mysqli::query2 and get a $result:

 $result = $connection->query($sql);
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Display data using mysqli_result::fetch_object4:

 echo "<pre>"; echo "No \t"; echo "ID \t"; echo "Firstname \t"; echo "Lastname \n"; $no = 1; /* variabel $no */ /* loop while */ while ( $row = $result->fetch_object() ) { echo $no . "\t"; echo $row->id . "\t"; echo $row->firstname . "\t\t"; echo $row->lastname . "\n"; $no++; /* increment */ } echo "</pre>";
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Close connection using mysqli::close5:

 $connection->close();
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Source Code:

3. PDO6

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Execute query and get a $result:

 $result = $connection->query($sql);
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Display Data:

 echo "<pre>"; echo "No \t"; echo "ID \t"; echo "Firstname \t"; echo "Lastname \n"; $no = 1; /* variabel $no */ /* loop foreach */ foreach ( $result as $row ) { echo $no . "\t"; echo $row->id . "\t"; echo $row->firstname . "\t\t"; echo $row->lastname . "\n"; $no++; /* increment */ } echo "</pre>";
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Close connection:

 $connection = null;
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Source Code:

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Thank for reading :)

  1. php.net, "MySQL Improved Extension", accessed on date 21 december 2019 and from https://www.php.net/manual/en/book.mysqli.php ↩

  2. php.net, "mysqli::query", accessed on date 22 december 2019 and from https://www.php.net/manual/en/mysqli.query.php ↩

  3. php.net, "mysqli_result::fetch_assoc", accessed on date 23 december 2019 and from https://www.php.net/manual/en/mysqli-result.fetch-assoc.php ↩

  4. php.net, "mysqli_result::fetch_object", accessed on date 23 december 2019 and from https://www.php.net/manual/en/mysqli-result.fetch-object.php ↩

  5. php.net, "mysqli::close", accessed on date 21 december 2019 and from https://www.php.net/manual/en/mysqli.close.php ↩

  6. php.net, "PDO::__construct", accessed on date 21 december 2019 and from https://www.php.net/manual/en/pdo.construct.php  ↩

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