DBA_TAB_STATISTICS显示数据库中所有表的优化器统计信息。它的列与ALL_TAB_STATISTICS中的列相同。
ALL_TAB_STATISTICS显示当前用户可以访问的表的优化器统计信息。
USER_TAB_STATISTICS显示当前用户拥有的表的优化器统计信息。此视图不显示所有者列。
|
Column |
Datatype |
NULL |
Description |
|
OWNER |
VARCHAR2(30) |
|
Owner of the object
对象的owner |
|
TABLE_NAME |
VARCHAR2(30) |
|
Name of the table
表名 |
|
PARTITION_NAME |
VARCHAR2(30) |
|
Name of the partition
分区名 |
|
PARTITION_POSITION |
NUMBER |
|
Position of the partition within the table
分区在表中的位置 |
|
SUBPARTITION_NAME |
VARCHAR2(30) |
|
Name of the subpartition
子分区的名字 |
|
SUBPARTITION_POSITION |
NUMBER |
|
Position of the subpartition within the partition
子分区在表中的位置 |
|
OBJECT_TYPE |
VARCHAR2(12) |
|
Type of the object:
-
TABLE
-
PARTITION
-
SUBPARTITION
表的类型：
表
分区表
子分区表 |
|
NUM_ROWS |
NUMBER |
|
Number of rows in the object
表中有多少行记录 |
|
BLOCKS |
NUMBER |
|
Number of used blocks in the object
表有多少块 |
|
EMPTY_BLOCKS |
NUMBER |
|
Number of empty blocks in the object
表中空块的数量 |
|
AVG_SPACE |
NUMBER |
|
Average available free space in the object
对象中可用的平均空闲空间 |
|
CHAIN_CNT |
NUMBER |
|
Number of chained rows in the object
表中发生行迁移或者行链接的数量 |
|
AVG_ROW_LEN |
NUMBER |
|
Average row length, including row overhead
平均行长度，包括行开销 |
|
AVG_SPACE_FREELIST_BLOCKS |
NUMBER |
|
Average freespace of all blocks on a freelist
自由列表中所有块的平均自由空间 |
|
NUM_FREELIST_BLOCKS |
NUMBER |
|
Number of blocks on the freelist
自由列表上的块数 |
|
AVG_CACHED_BLOCKS |
NUMBER |
|
Average number of blocks in the buffer cache
缓冲区缓存中的平均块数 |
|
AVG_CACHE_HIT_RATIO |
NUMBER |
|
Average cache hit ratio for the object
对象的平均缓存命中率 |
|
SAMPLE_SIZE |
NUMBER |
|
Sample size used in analyzing the table
分析表时的采样比例 |
|
LAST_ANALYZED |
DATE |
|
Date of the most recent time the table was analyzed
最近一次分析表的时间 |
|
GLOBAL_STATS |
VARCHAR2(3) |
|
Indicates whether statistics were calculated without merging underlying partitions (YES) or not (NO)
作为一个整体（分区表）表的统计的是否准确表示是否被用户统计信息 ( YES ) or ( NO ) |
|
USER_STATS |
VARCHAR2(3) |
|
Indicates whether statistics were entered directly by the user (
YES
) or not (
NO
)
表示是否被用户统计信息 ( YES ) or ( NO ) |
|
STATTYPE_LOCKED |
VARCHAR2(5) |
|
Type of statistics lock:
统计信息的类型：
data
cache
all：表示统计信息被锁定 |
|
STALE_STATS |
VARCHAR2(3) |
|
Indicates whether statistics for the object are stale (YES) or not (NO)
统计信息是否过期（yes 过期）或者（no 未过期） |