> For the complete documentation index, see [llms.txt](https://docs.pentaho.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pentaho.com/pdia-data-integration/10.2-data-integration/pdi-transformation-steps-reference-overview/query-metadata-from-a-database-article/options-query-from-database/fields-tab.md). # Fields tab ![Query metadata from Database step Fields tab](/files/bYdmSee8Y4NqYZKkS40S) You use the **Fields** tab to display all the fields within the JDBC discovery type. Click the **Get fields** button to display all the fields associated with each discovery type in the **Field name** column. **Optional**: Use the **Rename to** column to rename the field names. The new names will be available in any downstream transformation step. | JDBC Metadata Discovery Type | Field name | Description | | ------------------------------ | ---------------------------------------------------------------------------------- | ------------------------------------------------- | | **Catalog** | `catalog` | Name of the database catalog | | **Schemas** | `catalog` | Name of the database catalog | | `schema` | Name of the database schema | | | **Tables** | `catalog` | Name of the database catalog | | `schema` | Name of the database schema | | | `ref_generation` | Reference generation | | | `remarks` | Remarks | | | `self_referencing_column_name` | A column that refers to another column in the same table | | | `table_name` | Name of the database table | | | `table_type` | Type of the database table | | | `type_catalog` | Type catalog | | | `type_name` | Type name | | | `type_schema` | Type schema | | | **Columns** | `buffer_length` | Length of the buffer for specific data types | | `char_octet_length` | Maximum length, in bytes, for binary data, character data, or text and image data. | | | `column_default` | Default value of the column | | | `column_name` | Name of the column | | | `column_size` | Number of characters or digits of the data | | | `data_type` | Data type of the column | | | `decimal_digits` | Number of digits after the decimal point | | | `is_autoincrement` | Whether the column implements automatic increments | | | `is_generated_column` | Whether the column is generated | | | `is_nullable` | Whether the column allows null values. | | | `nullable` | Column is nullable | | | `number_precision_radix` | The base sytsem used for numeric precision (usually base 2 or 10) | | | `ordinal_position` | The location of the column ordering within a table or query output | | | `pentaho_data_type` | Maps to the custom Pentaho data type | | | `pentaho_data_type_int` | Maps to the custom Pentaho integer data type | | | `remarks` | Remarks | | | `schema` | Name of the database schema | | | `scope_catalog` | Catalog that lies within a scope | | | `scope_schema` | Schema that lies within a scope | | | `scope_table` | Table that lies within a scope. | | | `source_data_type` | Data type within a source | | | `sql_data_type` | SQL data type for a column | | | `sql_datetime_sub` | SQL date/time sub | | | `table_name` | Name of a table in the database | | | `type_name` | Name of a type in a database | | | **Primary Keys** | `catalog` | Name of the database catalog | | `column_name` | Name of the column | | | `key_sequence` | Sequence of the primary key | | | `pk_name` | Name of the primary key | | | `schema` | Name of the database schema | | | `table_name` | Name of a table in the database | | | **Foreign Keys** | `deferrability` | Whether the primary key have deferred constraints | | `delete_rule` | Delete rule for primary key | | | `fk_column_name` | Name of the foreign key column | | | `fk_name` | Name of the foreign key | | | `fk_table_schema` | Schema in the foreign key table | | | `key_sequence` | Sequence of the foreign key | | | `pk_column_name` | Name of the column in the primary key | | | `pk_name` | Name of the primary key | | | `pk_table_catalog` | Name of the catalog to which the primary key's table belongs | | | `pk_table_name` | Name of the table in the primary key | | | `pk_table_schema` | Schema in the primary key table | | | `update_rule` | Update rule for primary key | | --- # Agent Instructions This documentation is published with GitBook. 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