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CREATEINDEX Statement Details
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CREATEINDEX [#]filenumber%,indexname$,unique%,columnname$[,columnname$]
Usage Notes
■ When you initially open a table, the current index is the NULL index.
The NULL index represents the order in which records were added to the
file.
■ Once an index has been created, it can be used any number of times until
it is deleted from the database.
■ DELETE, INSERT, and UPDATE operations affect all indexes in a table.
Each of these operations automatically updates all indexes. INSERT or
UPDATE will fail if the operation produces a nonunique index value in
any index defined as unique-only. DELETE, INSERT, and UPDATE operations
are not affected by SETINDEX.
See: ◄DELETE Statement► ◄INSERT Statement►
◄SETINDEX Statement► ◄UPDATE Statement►
■ Use SETINDEX to make an index the current index and to impose its order
on the presentation of records in a table.
■ The maximum number of indexes per table is 28.
■ Columns that are arrays, user-defined types, or strings longer than 255
characters cannot be indexed.
■ The argument indexname$ is the name of the index until the index is
explicitly deleted.
■ A nonzero value for the argument unique% indicates the index is unique;
no two indexed values can be the same.
■ A value of zero for unique% means the indexed values need not be unique.
■ If more than one columnname$ is given, CREATEINDEX defines an index
based on the combination of their values.
■ The argument columnname$ must appear in the corresponding TYPE statement
used when the table was created.