In the context of MySQL, what are the best practices for efficiently transferring data between tables and performing updates within a single query?

When transferring data between tables and performing updates within a single query in MySQL, the best practice is to use the `INSERT INTO ... SELECT` statement for transferring data efficiently and the `UPDATE ... JOIN` statement for updating records based on a condition. This allows you to avoid multiple queries and reduce the overhead of processing data on the server side. 

// Transfer data from one table to another efficiently
$query = "INSERT INTO new_table (column1, column2)
          SELECT column1, column2
          FROM old_table
          WHERE condition";

$result = mysqli_query($connection, $query);

// Perform updates within a single query
$query = "UPDATE table1
          JOIN table2 ON table1.id = table2.id
          SET table1.column = value
          WHERE condition";

$result = mysqli_query($connection, $query);

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