Documentation & API reference
Field Storage API
Implements 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.
File
- drupal/
core/ modules/ field/ field.attach.inc, line 11 - Field attach API, allowing entities (nodes, users, ...) to be 'fieldable'.
Functions
Name |
Location | Description |
|---|---|---|
| hook_field_display_alter |
drupal/ |
Alters the display settings of a field before it is displayed. |
| hook_field_display_ENTITY_TYPE_alter |
drupal/ |
Alters the display settings of a field before it is displayed. |
| hook_field_extra_fields_display_alter |
drupal/ |
Alters the display settings of pseudo-fields before an entity is displayed. |
| hook_field_info_max_weight |
drupal/ |
Returns the maximum weight for the entity components handled by the module. |
| hook_field_storage_create_field |
drupal/ |
Act on creation of a new field. |
| hook_field_storage_delete |
drupal/ |
Delete all field data for an entity. |
| hook_field_storage_delete_field |
drupal/ |
Act on deletion of a field. |
| hook_field_storage_delete_instance |
drupal/ |
Act on deletion of a field instance. |
| hook_field_storage_delete_revision |
drupal/ |
Delete a single revision of field data for an entity. |
| hook_field_storage_details |
drupal/ |
Reveal the internal details about the storage for a field. |
| hook_field_storage_details_alter |
drupal/ |
Perform alterations on Field API storage details. |
| hook_field_storage_info |
drupal/ |
Expose Field API storage backends. |
| hook_field_storage_info_alter |
drupal/ |
Perform alterations on Field API storage types. |
| hook_field_storage_load |
drupal/ |
Load field data for a set of entities. |
| hook_field_storage_pre_insert |
drupal/ |
Act before the storage backends insert field data. |
| hook_field_storage_pre_load |
drupal/ |
Act before the storage backends load field data. |
| hook_field_storage_pre_update |
drupal/ |
Act before the storage backends update field data. |
| hook_field_storage_query |
drupal/ |
Execute a Drupal\Core\Entity\EntityFieldQuery. |
| hook_field_storage_write |
drupal/ |
Write field data for an entity. |
| hook_field_widget_properties_ENTITY_TYPE_alter |
drupal/ |
Alters the widget properties of a field instance on a given entity type before it gets displayed. |
Constants
|
Name |
Location | Description |
|---|---|---|
| FIELD_STORAGE_INSERT |
drupal/ |
Argument for an insert operation. |
| FIELD_STORAGE_UPDATE |
drupal/ |
Argument for an update operation. |