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CREATEINDEX Statement Details
  Summary  Details  Example                Contents  Index  Back
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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.