You can add an index to or remove an index from a column at any time by using either the Data Designer (RBDefine) or the CREATE INDEX or DROP INDEX commands. When you use the database-building menus to define a table, you can index columns as you define them. When you define a table using CREATE TABLE, you must add the index after you define the table.
Valid names must start with a letter, and can include the following characters:
•Letters (A-Z)
•Numbers (0-9)
•# (pound sign)
•_ (underscore)
•$ (dollar sign)
•% (percent sign)
To speed up some operations, remove the indexes from the columns before the operation and then rebuild the indexes after the operation finishes. For example, you can load a large number of rows into a table without RULES by using the LOAD and INSERT commands or by using GATEWAY to import data. First, you remove the indexes from the columns in the table, then load the records, and finally rebuild the indexes. This method speeds up processing because all of the data writes to file 2 occur at the same time, followed by all of the index writes to file 3.
When dropping and creating indexes constantly, it is recommended that you maintain the index file and perform a PACK on the indexes. Use the PACK KEYS in single-user mode with MULTI set to OFF, or PACK INDEX in a multi-user mode with MULTI set to ON.
