DB2 降低高水位线、刷新统计信息
db2 connect to DBNAME
db2 reorg table SCHEMANAME.TABLENAME allow read access
db2 runstats on table SCHEMANAME.TABLENAME on all columns with distribution and detailed indexes all
查看统计信息使用：
db2 "SELECT CARD,STATS_TIME FROM SYSCAT.TABLES WHERE TABNAME = 'TABLENAME'"
查看高水位线使用：
db2 list tablespaces show detail
