Caché ObjectScript Reference - InterSystems Documentation

Caché ObjectScript Functions$INCREMENT and Transaction ProcessingThe common usage for $INCREMENT is to increment a counter before adding a new entryto a database. $INCREMENT provides a way to do this very quickly, avoiding the use ofthe LOCK command and, in distributed environments, avoiding synchronous network trips.The trade-off for this is that the counter is not locked. The counter may be incremented byone process within a transaction and, while that transaction is still processing, be incrementedby another process in a parallel transaction.In the event either transaction (or any other transaction that uses $INCREMENT) must berolled back (with the TROLLBACK command), counter increments are ignored. The countervariables are not decremented since it is not clear whether the resulting counter value wouldbe valid. In all likelihood, such a rollback would be disastrous for other transactions.See Also• TROLLBACK command• $GET function• $ZINCREMENT function• Using ObjectScript for Transaction Processing in Using Caché ObjectScript$INUMBERValidates a numeric value and converts it to internal format.$INUMBER(fnumber,format,erropt)$IN(fnumber,format,erropt)ParametersfnumberformaterroptThe numeric value to be converted to the internal format. It can be anumeric or string value, a variable name, or any valid Caché ObjectScriptexpression.A format specification indicating which external numeric formats are validrepresentations of numbers. It is a string consisting of one or more validformat codes described below.Optional — The expression returned if fnumber is considered invalidbased on format.224 Caché ObjectScript Reference