SYSAGGREGATES
The sysaggregates system catalog table records
user-defined aggregates (UDAs). The sysaggregates table has
the following columns.
| Column | Type | Explanation |
|---|---|---|
| name | VARCHAR(128) | Name of the aggregate |
| owner | CHAR(32) | Name of the owner of the aggregate |
| aggid | SERIAL | Unique code identifying the aggregate |
| init_func | VARCHAR(128) | Name of initialization UDR |
| iter_func | VARCHAR(128) | Name of iterator UDR |
| combine_func | VARCHAR(128) | Name of combine UDR |
| final_func | VARCHAR(128) | Name of finalization UDR |
| handlesnulls | BOOLEAN | NULL-handling indicator:
|
Each user-defined aggregate has one entry in sysaggregates that is uniquely identified by its identifying code (the aggid value). Only user-defined aggregates (aggregates that are not built in) have entries in sysaggregates.
Both a simple index on the aggid column and a composite index on the name and owner columns require unique values.