Cause: A datatype or subtype specifier
was mistakenly used in place of a constant, variable, or expression. For
example, the code might look like IF emp_count > number THEN … —
illegal; NUMBER is a datatype specifier
Action: Replace the datatype or subtype
specifier with a valid constant, variable, or expression.

Relared Errors:
PLS-00331:
illegal reference to string
PLS-00332:
string is not a valid prefix for a qualified name
PLS-00333:
string must match an object-table alias in this
context
PLS-00334:
string matches table or view without an alias
PLS-00335: a
package name conflicts with an existing object
PLS-00336:
non-object-table string illegal in this context
PLS-00337:
string matches too many object table aliases
PLS-00338:
unable to resolve string as a column or row
expression
PLS-00339:
string matches object-table without a REF or VALUE
modifier
PLS-00341:
declaration of cursor `string` is incomplete or
malformed