Purpose of CHARACTER BINARY and MEMO BINARY Fields

• Microsoft Visual FoxPro for Windows, version 3.0

SUMMARY

Visual FoxPro version 3.0 introduces several new data types including Character(binary) and Memo(binary). This article describes the purpose and implementation of these two new data types.

MORE INFORMATION

The Character(binary) and Memo(binary) data types are provided for fields that should not be translated if the table is opened using a different code page. If the table is converted to another code page, the binary fields will not be translated. In all other respects, the Character(binary) and Memo(binary) fields are identical to the existing Character and Memo fields.

You might use binary fields to store:

• Unsupported graphic images. For example, SQL SERVER contains unsupported graphic images that could be selected into a memo field.
• Encrypted passwords that use the extended ASCII character set.
• Compiled code.
• FoxPro commands that contain strings that use the extended character set. For example, if a memo field or character field contains FoxPro code that references field names, these field names would be changed by a change in a code page if they used characters from the extended character set. However, the field names of the tables themselves would not be changed by a change in a code page.

To specify that a field is going be binary with the CREATE or ALTER TABLE commands, use the NOCPTRANS clause, as in this example:

   CREATE TABLE mytab (cLastName C(35) NOCPTRANS))

The TYPE function will return 'M' or 'C' for the binary memo or binary character field. This return value is the same as for a regular memo or character field.