Migrating databases using phpMyAdmin's tracking mechanism

Question

In a development database, I have phpMyAdmin Tracking enabled on all tables. It logs all the changes I make to the tables\' structures (in this case I\'m not interested in d

Answer 1

I don't have anything that creates an incremental diff between two databases but here's the script I use to compare two MySQL databases:

setAttribute(PDO::ATTR_EMULATE_PREPARES, FALSE); // Try to use the driver's native prepared statements.
    $db1_con->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); // Let's use exceptions so we can try/catch errors.
}catch(PDOException $e){
    echo "
Connection failed for $db1_host: " . $e->getMessage() . '
';
    exit;
}

try{
    $db2_con = new PDO("mysql:host=$db2_host;dbname=information_schema", $db2_username, $db2_password);
    $db2_con->setAttribute(PDO::ATTR_EMULATE_PREPARES, FALSE); // Try to use the driver's native prepared statements.
    $db2_con->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); // Let's use exceptions so we can try/catch errors.
}catch(PDOException $e){
    echo "
Connection failed for $db2_host: " . $e->getMessage() . '
';
    exit;
}

if (NULL !== $db1_con && NULL !== $db2_con){
    echo "
Column Analysis
";
    $sql = 'SELECT * FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = ? ORDER BY TABLE_NAME, ORDINAL_POSITION';
    $statement1 = $db1_con->prepare($sql);
    $statement1->bindValue(1, $db1_dbname);

    $statement2 = $db2_con->prepare($sql);
    $statement2->bindValue(1, $db2_dbname);

    if (TRUE === $statement1->execute()){
        while ($row = $statement1->fetch(PDO::FETCH_ASSOC)){
            $db1_tables[$row['TABLE_NAME']][$row['COLUMN_NAME']] = array();
            foreach ($row AS $key => $value){
                $db1_tables[$row['TABLE_NAME']][$row['COLUMN_NAME']][$key] = $value;
            }
        }
    }

    if (TRUE === $statement2->execute()){
        while ($row = $statement2->fetch(PDO::FETCH_ASSOC)){
            $db2_tables[$row['TABLE_NAME']][$row['COLUMN_NAME']] = array();
            foreach ($row AS $key => $value){
                $db2_tables[$row['TABLE_NAME']][$row['COLUMN_NAME']][$key] = $value;
            }
        }
    }

    foreach ($db1_tables AS $table => $info){
        if (!isset($db2_tables[$table])){
            echo "
Table $table does not exist in the SECOND database!
";
        }else{
            foreach ($info AS $column => $data){
                if (!isset($db2_tables[$table][$column])){
                    echo "
Column $column does not exist in table $table in the SECOND database!
";
                }else{
                    if (count($data)){
                        foreach ($data AS $key => $value){
                            if ($db1_tables[$table][$column][$key] !== $db2_tables[$table][$column][$key]){
                                echo "
Column $column in table $table has differing characteristics for $key (". $db1_tables[$table][$column][$key] ." vs. ". $db2_tables[$table][$column][$key] .")
";
                            }
                        }
                    }
                }
            }
        }
    }

    foreach ($db2_tables AS $table => $info){
        if (!isset($db1_tables[$table])){
            echo "
Table $table does not exist in the FIRST database!
";
        }else{
            foreach ($info AS $column => $data){
                if (!isset($db1_tables[$table][$column])){
                    echo "
Column $column does not exist in table $table in the FIRST database!
";
                }else{
                    if (count($data)){
                        foreach ($data AS $key => $value){
                            if ($db2_tables[$table][$column][$key] !== $db1_tables[$table][$column][$key]){
                                echo "
Column $column in table $table has differing characteristics for $key (". $db2_tables[$table][$column][$key] ." vs. ". $db1_tables[$table][$column][$key] .")
";
                            }
                        }
                    }
                }
            }
        }
    }
    echo "
Constraint Analysis
";

    $sql = 'SELECT * FROM information_schema.KEY_COLUMN_USAGE WHERE TABLE_SCHEMA = ? ORDER BY TABLE_NAME, ORDINAL_POSITION';
    $statement1 = $db1_con->prepare($sql);
    $statement1->bindValue(1, $db1_dbname);

    $statement2 = $db2_con->prepare($sql);
    $statement2->bindValue(1, $db2_dbname);

    if (TRUE === $statement1->execute()){
        while ($row = $statement1->fetch(PDO::FETCH_ASSOC)){
            foreach ($row AS $key => $value){
                $db1_constraints[$row['TABLE_NAME']][$row['COLUMN_NAME']][$key] = $value;
            }
        }
    }

    if (TRUE === $statement2->execute()){
        while ($row = $statement2->fetch(PDO::FETCH_ASSOC)){
            foreach ($row AS $key => $value){
                $db2_constraints[$row['TABLE_NAME']][$row['COLUMN_NAME']][$key] = $value;
            }
        }
    }

    foreach ($db1_constraints AS $table => $info){
        foreach ($info AS $column => $data){
            if (isset($db2_constraints[$table][$column])){
                if (count($data)){
                    foreach ($data AS $key => $value){
                        if ('CONSTRAINT_NAME' !== $key && $db1_constraints[$table][$column][$key] !== $db2_constraints[$table][$column][$key]){
                            echo "
Column $column in table $table has differing characteristics for $key (". $db1_constraints[$table][$column][$key] ." vs. ". $db2_constraints[$table][$column][$key] .")
";
                        }
                    }
                }
            }else{
                echo "
Column $column in table $table is missing a constraint in the SECOND database!
";
            }
        }
    }

    foreach ($db2_constraints AS $table => $info){
        foreach ($info AS $column => $data){
            if (isset($db1_constraints[$table][$column])){
                if (count($data)){
                    foreach ($data AS $key => $value){
                        if ('CONSTRAINT_NAME' !== $key && $db2_constraints[$table][$column][$key] !== $db1_constraints[$table][$column][$key]){
                            echo "
Column $column in table $table has differing characteristics for $key (". $db2_constraints[$table][$column][$key] ." vs. ". $db1_constraints[$table][$column][$key] .")
";
                        }
                    }
                }
            }else{
                echo "
Column $column in table $table is missing a constraint in the FIRST database!
";
            }
        }
    }
}
?>

Edited to add code that shows differences in constraints as well.