--收集Oracle统计信息BEGIN DBMS_STATS.GATHER_TABLE_STATS(OWNNAME =gt;--收集oracle统计信息begin dbms_stats.gather_table_stats(ownname => 'owner_name', --数据库用户名tabname => 'table_name', --表名partname => 'partition_name', --分区名estimate_percent => dbms_stats.auto_sample_size,method_opt => 'for all columns size repeat',degree => dbms_stats.auto_degree,cascade => true);end;--查询表的统计信息SELECT *FROM DBA_TAB_STATISTICS S WHERE S.OWNER = 'OWNER_NAME' --数据库用户名AND S.TABLE_NAME = 'TABLE_NAME' --表名ORDER BY S.LAST_ANALYZED DESC;--Oracle统计信息DBMS_STATS.gather_table_stats (ownname varchar2,tabname varchar2,partname varchar2 default null,estimate_percent number default to_estimate_percent_type(get_param('ESTIMATE_PERCENT')),block_sample boolean default FALSE,method_opt varchar2 default get_param('METHOD_OPT'),degree number default to_degree_type(get_param('DEGREE')),granularity varchar2 default get_param('GRANULARITY'),cascade boolean default to_cascade_type(get_param('CASCADE')),stattab varchar2 default null, statid varchar2 default null,statown varchar2 default null,no_invalidate boolean default to_no_invalidate_type(get_param('NO_INVALIDATE')),stattype varchar2 default 'DATA',force boolean default FALSE);/*参数说明:ownname: 要分析表的拥有者tabname: 要分析的表名.
partname: 分区的名字,只对分区表或分区索引有用.
estimate_percent:采样行的百分比,取值范围[0.000001,100],null为全部分析,不采样. 常量:DBMS_STATS.AUTO_SAMPLE_SIZE是默认值,由oracle决定最佳取采样值.
block_sapmple:是否用块采样代替行采样.
method_opt: 决定histograms信息是怎样被统计的.method_opt的取值如下:for all columns:统计所有列的histograms.
for all indexed columns:统计所有indexed列的histograms.
for all hidden columns:统计你看不到列的histograms for columns SIZE| REPEAT | AUTO | SKEWONLY:统计指定列的histograms.N的取值范围[1,254]; REPEAT上次统计过的histograms;AUTO由oracle决定N的大小;SKEWONLY multiple end-points with the same value which is what we define by "there is skew in the datadegree: 设置收集统计信息的并行度.默认值为null.granularity:Granularity of statistics to collect ,only pertinent if the table is partitioned.cascade: 是收集索引的信息.默认为falase.stattab 指定要存储统计信息的表,statid如果多个表的统计信息存储在同一个stattab中用于进行区分.statown存储统计信息表的拥有者.以上三个参数若不指定,统计信息会直接更新到数据字典.no_invalidate: Does not invalidate the dependent cursors if set to TRUE. The procedure invalidates the dependent cursorsimmediately if set to FALSE.force: 即使表锁住了也收集统计信息*/--例子:execute dbms_stats.gather_table_stats(ownname => 'owner',tabname => 'table_name' ,estimate_percent => null ,method_opt => 'for all indexed columns' ,cascade => true);--GATHER_INDEX_STATS--==========================BEGIN SYS.DBMS_STATS.GATHER_INDEX_STATS (OwnName => 'ABC',IndName => 'IDX_FUNC_ABC',Estimate_Percent => 10,Degree => SYS.DBMS_STATS.DEFAULT_DEGREE,No_Invalidate => FALSE);END;，