[20211206]分析表取样最小大小是多少.txt

[20211206]分析表取样最小大小是多少.txt --//别人问的问题，很容易测试出来。 1.环境： SCOTT@book> @ ver1 PORT_STRING                    VERSION        BANNER ------------------------------ -------------- -------------------------------------------------------------------------------- x86_64/Linux 2.4.xx            11.2.0.4.0     Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production 2.测试： SCOTT@book> execute sys.dbms_stats.gather_table_stats ( OwnName => user,TabName => 'dept',Estimate_Percent => 0.00000000001); BEGIN sys.dbms_stats.gather_table_stats ( OwnName => user,TabName => 'dept',Estimate_Percent => 0.00000000001); END; * ERROR at line 1: ORA-20001: Illegal sample percent .00000000001: must be in the range [0.000001,100] ORA-06512: at "SYS.DBMS_STATS", line 24281 ORA-06512: at "SYS.DBMS_STATS", line 24332 ORA-06512: at line 1 --//最小也就是1e-6.实际上你设置很小的取样，实际取样还是可能不同的。