ctGetNextSequenceValue
Declaration
NINT ctGetNextSequenceValue(LONG seqhnd, pLONG8 pnxtval, pNINT punkval);
Description
Reads the next value for the specified sequence. The next value of a sequence can be one of the following:
Sequence values are stored in the database in which they are defined, and persist between each call to the ctSetCurrentSequenceValue() or ctGetNextSequenceValue() function.
The value of a sequence set by the ctGetNextSequenceValue() function persists in the database until the next call to ctSetCurrentSequenceValue() or ctGetNextSequenceValue() for the sequence, or until the sequence is deleted from the database.
Reaching the End of a Terminating Sequence
If the sequence is a terminating sequence, and ctGetNextSequenceValue() 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, ctGetNextSequenceValue() continues to return the unknown value for the specified sequence until it is reset to a new value with the ctSetCurrentSequenceValue() function, or its definition is changed to a cycling sequence by the ctSetSequenceAttrs() function.
After changing the sequence definition to cycle, the first use of ctGetNextSequenceValue() for the sequence sets and returns its initial value.
Return Values
Value |
Symbolic Constant |
Value |
Explanation |
---|---|---|---|
0 |
NO_ERROR |
0 |
Successfully created the sequence. |
900 |
SEQDUP_ERR |
900 |
A sequence having the specified name already exists. |
903 |
SEQTYP_ERR |
903 |
The specified sequence type contains an invalid combination of sequence type options. |
904 |
SEQINI_ERR |
904 |
The initial value specified for the sequence is out of range. |
905 |
SEQCUR_ERR |
905 |
The current value specified for the sequence is out of range. |
906 |
SEQLIM_ERR |
906 |
The limit value specified for the sequence is out of range. |
907 |
SEQINC_ERR |
907 |
The increment value specified for the sequence is out of range. |
901 |
SEQNAM_ERR |
901 |
Invalid sequence name specified (NULL, empty, or too long). |
902 |
SEQHND_ERR |
902 |
Invalid sequence handle. |
See c-treeACE Error Codes for a complete listing of valid error values.
Example
ctSEQATTR seqattr;
NINT rc;
/*
** Create an incrementing sequence that starts with 1, increments by 3, and
** terminates with 100.
*/
strcpy(seqattr.seqnam, "MyFirstSequence");
seqattr.seqini = 1;
seqattr.seqinc = 3;
seqattr.seqlim = 100;
seqattr.seqtyp = ctSEQINC | ctSEQTRM | ctSEQLIM;
if ((rc = ctCreateSequence(&seqattr))) {
printf("Error: Failed to create the sequence: %d\n", rc);
} else {
printf("Successfully created the sequence.\n");
}
See also
ctCreateSequence, ctDeleteSequence, ctOpenSequence, ctCloseSequence, ctGetSequenceAttrs, ctSetSequenceAttrs, ctGetCurrentSequenceValue, ctSetCurrentSequenceValue, ctGetNextSequenceValue