Field Storage API

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Implement a storage engine for Field API data.

The Field Attach API uses the Field Storage API to perform all "database access". Each Field Storage API hook function defines a primitive database operation such as read, write, or delete. The default field storage module, field_sql_storage.module, uses the local SQL database to implement these operations, but alternative field storage backends can choose to represent the data in SQL differently or use a completely different storage mechanism such as a cloud-based database.

Each field defines which storage backend it uses. The Drupal system variable 'field_storage_default' identifies the storage backend used by default.

See Field API for information about the other parts of the Field API.

Functions

Namesort descending Location Description
hook_field_display_alter modules/field/field.api.php Alters the display settings of a field before it gets displayed.
hook_field_display_ENTITY_TYPE_alter modules/field/field.api.php Alters the display settings of a field on a given entity type before it gets displayed.
hook_field_extra_fields_display_alter modules/field/field.api.php Alters the display settings of pseudo-fields before an entity is displayed.
hook_field_info_max_weight modules/field/field.api.php Returns the maximum weight for the entity components handled by the module.
hook_field_storage_create_field modules/field/field.api.php Act on creation of a new field.
hook_field_storage_delete modules/field/field.api.php Delete all field data for an entity.
hook_field_storage_delete_field modules/field/field.api.php Act on deletion of a field.
hook_field_storage_delete_instance modules/field/field.api.php Act on deletion of a field instance.
hook_field_storage_delete_revision modules/field/field.api.php Delete a single revision of field data for an entity.
hook_field_storage_details modules/field/field.api.php Reveal the internal details about the storage for a field.
hook_field_storage_details_alter modules/field/field.api.php Perform alterations on Field API storage details.
hook_field_storage_info modules/field/field.api.php Expose Field API storage backends.
hook_field_storage_info_alter modules/field/field.api.php Perform alterations on Field API storage types.
hook_field_storage_load modules/field/field.api.php Load field data for a set of entities.
hook_field_storage_pre_insert modules/field/field.api.php Act before the storage backends insert field data.
hook_field_storage_pre_load modules/field/field.api.php Act before the storage backends load field data.
hook_field_storage_pre_update modules/field/field.api.php Act before the storage backends update field data.
hook_field_storage_query modules/field/field.api.php Execute an EntityFieldQuery.
hook_field_storage_write modules/field/field.api.php Write field data for an entity.
hook_field_widget_properties_ENTITY_TYPE_alter modules/field/field.api.php Alters the widget properties of a field instance on a given entity type before it gets displayed.

Constants

Namesort descending Location Description
FIELD_STORAGE_INSERT modules/field/field.attach.inc Argument for an insert operation.
FIELD_STORAGE_UPDATE modules/field/field.attach.inc Argument for an update operation.

File

modules/field/field.attach.inc, line 32
Field attach API, allowing entities (nodes, users, ...) to be 'fieldable'.