DDBuilder: Defining General Column Attributes (Superseded)

To define the attributes (i.e., data type, column length, and numeric precision) for each column in a table, do the following:

1. In the tree view, select the desired column to display the General Column properties page.

2. Enter data into the appropriate fields (each field is described under Fields).

Fields

Description

Provide a short description of the column contents.

Data Type

Select the column's data type (Native PRO/5 or typedef) by clicking on the appropriate item.

After the data type is selected, the list box below displays the defined types for the given group. (In Visual PRO/5 2.0, the maximum size for Integer and Unsigned Integer fields has been expanded from 4 to 6 bytes.)

Data Type	Description
Character string	Default data type.
Numeric	Free-format numbers.
Integer	Stored in fixed-length field of 1 to 6 bytes.
Unsigned integer	Similar to Integer, but values are always interpreted as positive numbers.
IEEE float	Industry-standard floating point format (8 bytes).
BCD float	Binary Coded Decimal representation.
Business math	Stored in fixed-length field of 8 bytes.
C float	Standard single precision floating point format for the current machine.
C double	Standard double precision floating point format for the current machine.

Length Type

Indicate whether the column has a variable length, fixed length or a padded length.

Traditional PRO/5 data formats are typically made up of variable-length character string and numeric columns that are terminated by the $0A$ line-feed character. The decimal equivalent of $0A$ is 10.

For existing record structures that contain several line-feed delimited columns containing substrings, define all but the last substring as fixed-length. Define the final substring in the record as variable-length, with a terminator of 10.

If a padded length is selected, specify the pad character in the Pad/Terminator box.

Length

Define the internal or stored size of the column. The size is based on the data type.

Data Type	Size
Character String	Up to 32,767 bytes.
Numeric	Up to 32,767 bytes.
Integer	1, 2, 3, or 4 bytes.
Unsigned integer	1, 2, 3, or 4 bytes.
IEEE float	N/A (always 8 bytes).
BCD float	N/A (always 8 bytes).
Business math	N/A (always 8 bytes).
C float	N/A (always 4 bytes).
C double	N/A (always 8 bytes).

Dim

If the column contains a repeating field (array), define the number of elements, up to 255. The default is 1, which implies an ordinary non-repeating field. (Only one- dimensional arrays are supported.)

Max Length

If the column has a variable length, define a length of up to 32,767 bytes.

Precision

Define the number of decimal places in a numeric column. Although the default is 2 decimal places, an integer between -1 and 16 can be specified. A value of -1 indicates floating point, or maximum precision. Precision takes effect when a value is assigned to the column upon inserting a record. For a data dictionary to be used by BBxPROGRESSION/4, the maximum precision is 14.