## QQQ Tables

The core type of object in a QQQ Instance is the Table. In the most common use-case, a QQQ Table may be the in-app representation of a Database table. That is, it is a collection of records (or rows) of data, each of which has a set of fields (or columns).

QQQ also allows other types of data sources (QQQ Backends) to be used as tables, such as File systems, API’s, Java enums or objects, etc. All of these backend types present the same interfaces (both user-interfaces, and application programming interfaces), regardless of their backend type.

### QTableMetaData

Tables are defined in a QQQ Instance in a `QTableMetaData` object. All tables must reference a QQQ Backend, a list of fields that define the shape of records in the table, and additional data to describe how to work with the table within its backend.

QTableMetaData Properties:

- `name` - String, Required - Unique name for the table within the QQQ Instance.

- `label` - String - User-facing label for the table, presented in User Interfaces. Inferred from `name` if not set.

- `backendName` - String, Required - Name of a QQQ Backend in which this table’s data is managed.

- `fields` - Map of String → QQQ Field, Required - The columns of data that make up all records in this table.

- `primaryKeyField` - String, Conditional - Name of a QQQ Field that serves as the primary key (e.g., unique identifier) for records in this table.

- `uniqueKeys` - List of UniqueKey - Definition of additional unique constraints (from an RDBMS point of view) from the table. e.g., sets of columns which must have unique values for each record in the table.

- `backendDetails` - QTableBackendDetails or subclass - Additional data to configure the table within its QQQ Backend.

- `automationDetails` - QTableAutomationDetails - Configuration of automated jobs that run against records in the table, e.g., upon insert or update.

- `customizers` - Map of String → QCodeReference - References to custom code that are injected into standard table actions, that allow applications to customize certain parts of how the table works.

- `parentAppName` - String - Name of a QQQ App that this table exists within.

- `icon` - QIcon - Icon associated with this table in certain user interfaces.

- `recordLabelFormat` - String - Java Format String, used with `recordLabelFields` to produce a label shown for records from the table.

- `recordLabelFields` - List of String, Conditional - Used with `recordLabelFormat` to provide values for any format specifiers in the format string. These strings must be field names within the table.

  - Example of using `recordLabelFormat` and `recordLabelFields`:

    // given these fields in the table:
    new QFieldMetaData("name", QFieldType.STRING)
    new QFieldMetaData("birthDate", QFieldType.DATE)

    // We can produce a record label such as "Darin Kelkhoff (1980-05-31)" via:
    .withRecordLabelFormat("%s (%s)")
    .withRecordLabelFields(List.of("name", "birthDate"))

- `sections` - List of QFieldSection - Mechanism to organize fields within user interfaces, into logical sections. If any sections are present in the table meta data, then all fields in the table must be listed in exactly 1 section. If no sections are defined, then instance enrichment will define default sections.

- `associatedScripts` - List of AssociatedScript - Definition of user-defined scripts that can be associated with records within the table.

- `enabledCapabilities` and `disabledCapabilities` - Set of Capability enum values - Overrides from the backend level, for capabilities that this table does or does not possess.