Problem Note 59481: Performance problems occur when joining a SAS® data set and a DB2 table
 |  |  |  |  |
In SAS® 9.4 TS1M3, you might encounter a problem in which it takes longer to process queries than it takes in previous releases of SAS. This problem occurs when you are using the DBKEY= data set option while joining a SAS data set with a DB2 table.
In order to match any missing values in the SAS data set, SAS includes a check for null values in the query that it passes to DB2. Often, this check results in DB2 performing a full-table scan, which occurs even if the DB2 column has been defined as NOT NULL.
If the DB2 column is defined as NOT NULL or you know that your SAS variable does not contain any missing values, you can work around this problem by using the LIBNAME or DBNULLKEYS= data set option and setting it to NO.
For more information about the DBNULLKEYS data set option, see the "DBKEY= Data Set Option" section of SAS/ACCESS® 9.4 for Relational Databases: Reference, Ninth Edition.
Click the Hot Fix tab in this note to access the hot fix for this issue.
Operating System and Release Information
| Product Family | Product | System | Product Release | SAS Release | ||
| Reported | Fixed* | Reported | Fixed* | |||
| SAS System | SAS/ACCESS Interface to DB2 | z/OS | 9.4_M3 | 9.4_M3 | 9.4 TS1M3 | 9.4 TS1M4 |