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Statements and Functions Used for Developing ISAM Databases
 
                     Statement or
Task                 function          Action
══════════════════   ═══════════════   ═════════════════════════════════════
Creating/accessing   OPEN (File I/O)   Opens an ISAM table (you specify
files and tables                       both the database file and the
                                       table).
 
                     CLOSE             Closes I/O to an ISAM table.
 
                     DELETETABLE       Removes a table and deletes any
                                       indexes based on the table from an
                                       ISAM database.
 
                     TYPE              Defines an ISAM table type that
                                       contains one or more table columns
                                       in an ISAM record.
 
Controlling          CREATEINDEX       Create indexes
presentation order
of data (indexing)   GETINDEX$         Returns the name of the current
                                       index for an ISAM table.
 
                     SETINDEX          Makes the specified ISAM table
                                       index the current index.
 
                     DELETEINDEX       Permanently removes an index from
                                       an ISAM database.
 
                     TEXTCOMP          Compares the relative order of two
                                       strings as they would be sorted by an
                                       ISAM index.
 
Changing position    MOVEFIRST,        Make the first, last, next, or
                     MOVELAST,         previous record the current
                     MOVENEXT,         record.
                     MOVEPREVIOUS
 
                     SEEKGT,           Cause the first matching record in
                     SEEKGE,           an ISAM table, according to the
                     SEEKEQ            current index, to become the
                                       current record.
 
Getting table        BOF               Tests whether the current position
information                            is at the beginning of an ISAM
                                       table.
 
                     EOF               Tests whether the current position
                                       is at the end of an ISAM table.
 
                     LOF               Returns the number of records in an
                                       ISAM table.
 
                     FILEATTR          Returns information about an ISAM
                                       table.
 
Exchanging data      INSERT            Adds a new record to an ISAM table.
 
                     RETRIEVE          Fetches the current record in an
                                       ISAM table and places its data
                                       into a variable.
 
                     UPDATE            Updates the current record in an
                                       ISAM table.
 
                     DELETE            Removes the current record from an
                                       ISAM table.
 
Processing           BEGINTRANS        Starts a transaction log of all
transactions                           operations.
 
                     COMMITTRANS       Commits all ISAM database
                                       transactions since the most recent
                                       BEGINTRANS statement.
 
                     CHECKPOINT        Forces the current state of all
                                       databases to be written to disk.
 
                     ROLLBACK          Restores the state of the database
                                       to what it was at a specified
                                       savepoint, or to the beginning of
                                       the transaction.
 
                     SAVEPOINT         Marks points within the transaction
                                       log to which the transaction can
                                       be rolled back.