db2 fetch first 10 rows

Fetch first n rows in db2 and rownum in oracle if you want to obtain the first n rows in db2, you only need to add fetch first n rows only, but there is no

Tags: SQL Server oracle keyword MySQL whereIn Oracle, if we ask for the first few rows of the table, use the keyword rownum Example: SELECT * from student where rownumIn MySQL, use the keyword limit Example: SELECT * FROM student limit 10 results in removing the first 10 rows of data or select * from student limit to r

"update db cfg for DBNAME using maxfilop n" Iv. Lock The default value of LOCKTIMEOUT is-1, which means no lock timeout will occur (for OLTP applications, this situation may be disastrous ). Even so, I often find that many DB2 users use LOCKTIMEOUT =-1. Set LOCKTIMEOUT to a very short time value, for example, 10 or 15 seconds. Wait for a long time on the lock will produce an avalanche effect on the lock. F

devices ). The constant opening and closing of files slows down the SQL response time and consumes the CPU cycle. To check whether DB2 is closing the file, run the following command: 1 db2 "get snapshot for database on DBNAME" and find the following rows: 1 Database files closed = 0 if the value of the preceding parameter is not 0, the value of MAXFILOP is inc

doing so is that the system can first scan data based on the most restrictive predicate definitions, effectively reducing the data processing pressure in the second or third predicate scan process, it also improves the overall SQL statement retrieval efficiency. 8. Delete unnecessary predicate ConditionsThe predicate condition in each SQL statement is processed by the system and occupies system resources. Therefore, if a condition is unnecessary, delete it from the SQL statement, to avoid unnec