How to Return Integer and Numeric Columns from MySQL as Integers and Numerics in PHP

How do I return integer and numeric columns from MySQL as integers and numerics in PHP?

The solution is to ensure that you are using the mysqlnd driver for php.

How do you know that you're not using mysqlnd?

When viewing php -i, there will be no mention of "mysqlnd". The pdo_mysql section will have something like this:

pdo_mysql

PDO Driver for MySQL => enabled Client API version => 5.1.72

How do you install it?

Most installation guides for L/A/M/P suggest apt-get install php5-mysql but the native driver for MySQL is installed by a different package: php5-mysqlnd. I found that this was available with the ppa:ondrej/php5-oldstable.

To switch to the new driver (on Ubuntu):

• Remove the old driver:
  
  apt-get remove php5-mysql
• Install the new driver:
  
  apt-get install php5-mysqlnd
• Restart apache2:
  
  service apache2 restart

How do I check that the driver is being used?

Now php -i will mention "mysqlnd" explicitly in the pdo_mysql section:

pdo_mysql

PDO Driver for MySQL => enabled
Client API version => mysqlnd 5.0.10 - 20111026 - $Id:      e707c415db32080b3752b232487a435ee0372157 $

PDO settings

Ensure that PDO::ATTR_EMULATE_PREPARES is false (check your defaults or set it):

$pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);

Ensure that PDO::ATTR_STRINGIFY_FETCHES is false (check your defaults or set it):

$pdo->setAttribute(PDO::ATTR_STRINGIFY_FETCHES, false);

Returned values

• Floating-point types (FLOAT, DOUBLE) are returned as PHP floats.
• Integer types (INTEGER, INT, SMALLINT, TINYINT, MEDIUMINT, BIGINT †) are returned as PHP integers.
• Fixed-Point types (DECIMAL, NUMERIC) are returned as strings.

† BIGINTs with a value greater than a 64 bit signed int (9223372036854775807) will return as a string (or 32 bits on a 32 bit system)

    object(stdClass)[915]
      public 'integer_col' => int 1
      public 'double_col' => float 1.55
      public 'float_col' => float 1.5
      public 'decimal_col' => string '1.20' (length=4)
      public 'bigint_col' => string '18446744073709551615' (length=20)

PHP - Make MySQL return integers

It depends on the mysql client driver.

• The original mysql client driver returned all data as strings.
• The "new" mysqlnd (native driver) returns strongly typed data where possible.

This driver has been the default since PHP 5.4, so you should already be using it.

You can use phpinfo() to find out which driver you are using for sure.
Look for the MySQL section and it will say something like:

Client API version  mysqlnd 5.0.11-dev 

How to get numeric types from MySQL using PDO?

I don't think having "numbers" can be done in PHP 5.2 :-(

In PHP 5.3, it becomes possible, if I remember correctly, when you are using the new (new as in PHP >= 5.3) mysqlnd (MySQL Native Driver) driver.

Well, after more digging through my bookmarks I found this article about mysqlnd : PDO_MYSQLND: The new features of PDO_MYSQL in PHP 5.3

It says this (quote) :

Advantages of using mysqlnd for PDO

mysqlnd returns native data types when
using Server-side Prepared Statements,
for example an INT column is returned
as an integer variable not as a
string. That means fewer data
conversions internally.

But this is PHP 5.3 only (provided your version of PHP 5.3 is compiled with mysqlnd (and not old libmysql)), and seems to only be the case for prepared statements :-(

Sorry...

A solution would be to have, on the PHP-side, a mapping-system (like an ORM -- see Doctrine ; just as an example of ORM : I don't know if it does what you're asking) to convert results coming from the DB to PHP datatypes...

And yes, this is bad if you want to use operators like === and !==, which are type-sensitive...

PDO SQLSRV and PDO MySQL return strings when fetching int or float

With PDO MySQL the underlying C API returns a structure of strings when calling mysql_fetch_row(). Since PHP is a loosely typed language that automatically casts to integer as necessary, I suspect the PDO developers chose to return them as-is. This would be faster than looking up each column type and dynamically casting to an integer / float.

Specifically regarding float, a native PHP float may be different than the original stored value when converted from a string. For example, MySQL columns support a precision while PHP floats do not. Leaving floats as a string from the database allows you more control (e.g. choosing to use a library with different precision).

MySQL integer field is returned as string in PHP

When you select data from a MySQL database using PHP the datatype will always be converted to a string. You can convert it back to an integer using the following code:

$id = (int) $row['userid'];

Or by using the function intval():

$id = intval($row['userid']);

Why not PDO_MySQL return integer?

Set PDO::ATTR_EMULATE_PREPARES to false, if you really need it with loosely-typed PHP

If mysql_fetch_row returns you int for SUM either (I never cared to check) - then it does some magic like if (ctype_digit($val)) $row[$key] = (int)$val; - so you can do in your DBAL

As far as I understand the way prepared statements works, it uses the same packet structure for either sending and retrieving data, and this packet contains data type.

It looks like that server can return data in 2 formats - native and mysqlnd, depends on the request type. A latter one can be interpreted by client library to cast resulting value.

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