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DYNAMIC-NEXT-VALUE(
sequence-expression, logical-dbname-expression , tenant-id ) |
If logical-dbname-expression contains the Unknown value (?), the AVM raises a run-time error.
If sequence-expression is a cycling sequence, and the DYNAMIC-NEXT-VALUE function increments the sequence beyond its upper limit (for positive increments) or decrements the sequence beyond its lower limit (for negative increments), the function sets and returns the initial value defined for the sequence.
If sequence-expression is a terminating sequence, and the DYNAMIC-NEXT-VALUE function attempts to increment the sequence beyond its upper limit (for positive increments) or decrement the sequence beyond its lower limit (for negative increments), the function returns the Unknown value (?) and leaves the current sequence value unchanged. Once a sequence terminates, DYNAMIC-NEXT-VALUE continues to return the Unknown value (?) for the specified sequence until it is reset to a new value with the DYNAMIC-CURRENT-VALUE statement, or its definition is changed to a cycling sequence. After changing the sequence definition to cycle, the first use of DYNAMIC-NEXT-VALUE for the sequence sets and returns its initial value.
If sequence-expression is a multi-tenant sequence in the database, each regular tenant has their own current value of the sequence. So, the same values are returned for each tenant that invokes this function. If the sequence is shared in a multi-tenant database, the values returned by this function are unique across all tenants in the database.
The value of a sequence set by the DYNAMIC-NEXT-VALUE function persists in the database until the next DYNAMIC-CURRENT-VALUE statement or DYNAMIC-NEXT-VALUE function is invoked for the sequence, or until the sequence is deleted from the database.
You cannot invoke the DYNAMIC-NEXT-VALUE function from within a WHERE clause. Doing so generates a compiler error because the value returned by the DYNAMIC-NEXT-VALUE function can result in ambiguous expressions. To use a result from the DYNAMIC-NEXT-VALUE function in a WHERE clause, assign the result to a variable and use the variable in the WHERE clause instead.
You can use any combination of the DYNAMIC-NEXT-VALUE function, DYNAMIC-CURRENT-VALUE function, DYNAMIC-CURRENT-VALUE statement, and their non-dynamic versions.