The SAP ASE query processor uses statistics about the tables, indexes, partitions, and columns in a query to estimate query costs. The query processor chooses the access method that it determines to be the least expensive. But to do so, it must have accurate statistics.
Some statistics are updated during query processing. Others are updated only when you run the update statistics command or create indexes.
update statistics helps SAP ASE make the best decisions by creating histograms for each major attribute of the local indexes for a partition, and creating densities for the composite attributes. Use update statistics when a large amount of data in a partitioned table has been added, changed, or deleted.
update statistics
update table statistics
update all statistics
update index statistics
delete statistics
update statistics titles partition smallvalues
See the Reference Manual: Commands.