Setting field name and type
Use the Column name edit box to set the field name. Note that the name of the field must be unique among all the field names in the table.
Field based on
Select the source type for creating the field. It can be one of the existing domains, a standard data type, e.g. INTEGER, DATE or CHAR, or a 'COMPUTED BY' expression if you want to calculate the field value using other fields' values.
|
Field based on |
Description |
|
Domain |
Makes the field based on the existing domain. Select the domain name from the Domain drop-down list on the Domain tab. You can also create a new domain, using the New domain button, or edit the selected domain with the Edit domain button (see Domain Editor to learn how to create/edit domains). |
|
Standard data type |
Makes the field based on the standard SQL datatype. Select the data type from the Type drop-down list on the Raw Data Type tab. For NUMERIC and DECIMAL data types set 1 - 15 digit precision and scale in the appropriate boxes; for CHAR and VARCHAR set length (in characters) and charset, for BLOB data type set segment size, subtype and charset. |
|
'COMPUTED BY' expression |
Specifies that the value of the field's data is calculated from expression at runtime and is therefore not allocated storage space in the database. Set the expression to calculate on the Calculated by tab, e.g.: (OLD_SALARY + OLD_SALARY * PERCENT_CHANGE / 100)
Note the following:
|
Not Null
Check this option to prevent the entry of NULL or unknown values in column. Not null affects all INSERT and UPDATE operations on a column.
Primary key
Check this option to include the field into the primary key. Note that if you include a field to a primary key, you should also make it Not Null to avoid an error.
Autoincrement value
Allows you to create a generator, a trigger or a procedure wrapper along with the field to simulate an autoincrement field. For more details see Defining autoincrement.
Support IB6/FireBird syntax
Check this option to enable support of InterBase 6.0 / FireBird syntax. Checked by default.
When you are done, click OK. The Compile Window appears, where you can commit the successful transaction, rollback transaction and return to the editor, or make some changes to the statements, rollback and recompile new definition.
|
See also: |
