Portability
Portability
Each database management system (DBMS) has it's own behaviors. For example, some databases capitalize field names in their output, some lowercase them, while others leave them alone. These quirks make it difficult to port your applications over to another database type. Doctrine strives to overcome these differences so your applications can switch between DBMS's without any changes. For example switching from sqlite to mysql.
The portability modes are bitwised, so they can be combined using | and removed using ^. See the examples section below on how to do this.
You can read more about the bitwise operators on the PHP website.
Portability Mode Attributes
Below is a list of all the available portability attributes and the description of what each one does:
| Name | Description |
|---|---|
| PORTABILITY_ALL | Turn on all portability features. This is the default setting. |
| PORTABILITY_DELETE_COUNT | Force reporting the number of rows deleted. Some DBMS's don't count the number of rows deleted when performingsimple DELETE FROM tablename queries. This mode tricks such DBMS's into telling the count by adding WHERE 1=1 to the end of DELETE queries. |
| PORTABILITY_EMPTY_TO_NULL | Convert empty strings values to null in data in and output. Needed because Oracle considers empty strings to be null, while most other DBMS's know the difference between empty and null. |
| PORTABILITY_ERRORS | Makes certain error messages in certain drivers compatible with those from other DBMS's |
| PORTABILITY_FIX_ASSOC_FIELD_NAMES | This removes any qualifiers from keys in associative fetches. Some RDBMS, like for example SQLite, will by default use the fully qualified name for a column in assoc fetches if it is qualified in a query. |
| PORTABILITY_FIX_CASE | Convert names of tables and fields to lower or upper case in all methods. The case depends on the field_case option that may be set to either CASE_LOWER (default) or CASE_UPPER |
| PORTABILITY_NONE | Turn off all portability features. |
| PORTABILITY_NUMROWS | Enable hack that makes numRows() work in Oracle. |
| PORTABILITY_EXPR | Makes DQL API throw exceptions when non-portable expressions are being used. |
| PORTABILITY_RTRIM | Right trim the data output for all data fetches. This does not applied in drivers for RDBMS that automatically right trim values of fixed length character values, even if they do not right trim value of variable length character values. |
Examples
Now we can use the setAttribute() method to enable portability for lowercasing and trimming with the following code:
// bootstrap.php
// ...
$conn->setAttribute(Doctrine_Core::ATTR_PORTABILITY,
Doctrine_Core::PORTABILITY_FIX_CASE | Doctrine_Core::PORTABILITY_RTRIM);
Enable all portability options except trimming
// bootstrap.php
// ...
$conn->setAttribute(Doctrine_Core::ATTR_PORTABILITY,
Doctrine_Core::PORTABILITY_ALL ^ Doctrine_Core::PORTABILITY_RTRIM);
Questions and Feedback
If you find a problem with the documentation or have a suggestion, please register and open a ticket.If you need support or have a technical question, you can post to the user mailing-list.
