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Article #25631: Can I alter the the data type of primary key on a table?

Problem:
I need to change the datatype of a field that is part of the Primary Key of
a table.  Can I do this without destroying the table and rebuilding it?

Solution:
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Note: This information applies to all InterBase versions.
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The SQL standard supplies no syntax for altering the datatype, scale, or length of columns.
The only 'standard compliant' way to alter those characteristics is to delete and recreate the field.
Since you can not delete part of a primary key, the only way to change the primary is to delete
the table.

source: Ann Harrison on the listserve

Last Modified: 24-OCT-00