Form Storage Mechanisms

A storage mechanism is defined by subclass I2CE_FormStorage_Mechanism which provides the methods to read, and possibly write, the data for any form with the given mechanism. If the data is stored in a database, it can sub-class I2CE_FormStorage_DB and provide read access to the data as a form by only defining one method, getRequiredFieldsQuery(). To make a storage mechanism writable, you only need to write a method which defines how to store a data field.

Once a storage mechanism is written, the data for that form can be queried via searches with limits.

The currently (or soon-to-be) available storage mechanisms are:

• entry: A vertical database storage mechanism which keeps a history of when and by who individual fields (data elements) were changed. This is the default storage mechanism, and the storage mechanism that was used in version prior to 3.2.
• flat: A horizontal database storage mechanism, where a row of a table corresponds to an instance of a form. The columns, or any SQL function, of the table are used to define the fields.
• multi_flat: A horizontal database storage mechanism similar to the flat storage mechanism but combining several identically structured tables. It is primarily intended for data collation.
• magicdata: A locale aware storage mechanism primarily intended for centrally maintained lists of data.
• CSV: A storage mechanism to read data from a CSV file
• Eval: A storage mechanism to populate and get records based on php function calls
• SDMX-HD: A storage mechanism to populate and get records based on SDMX-HD code lists.

Storage mechanisms are easy to write, and some other possibilities for storage mechanisms which could be added are for:

• Data stored in XML files.
• Data stored in a CSV file.

Much base functionality is provided in I2CE_FormStorage_Mechanism, although these methods may be overwritten to improve speed.

Aggregating Storage Mechansims

You may be in a situation in which you need to aggregate from several different instances of iHRIS Manage (or Qualify). You can mark a specific a storage mechanism, $storage_mechanism, as being aggregating by setting:

/modules/forms/storage_options/$storage_mechanism/componentized

to 1. Then each form $form that uses that storage mechanism, will be componetized.

At the moment, only the Multi-Flat storage mechanism is an aggregating storage mechanism.

Once the form-storage module is enabled, an instance of I2CE_Form has the method isComponentized() to check if a form is componentized. You can also check via I2CE_FormStorage::isComponentized($form)