DBA_SEGMENTS 数据字典 块数量和发生变化情况
Oracle® Database Reference

10g Release 2 (10.2)

http://docs.oracle.com/cd/B19306_01/server.102/b14237/statviews_4097.htm

ColumnDatatypeNULLDescriptionOWNERVARCHAR2(30) Username of the segment ownerSEGMENT_NAMEVARCHAR2(81) Name, if any, of the segmentPARTITION_NAMEVARCHAR2(30) Object Partition Name (Set to NULL for non-partitioned objects)SEGMENT_TYPEVARCHAR2(18) Type of segment: INDEX PARTITION, TABLE PARTITION, TABLE, CLUSTER, INDEX, ROLLBACK, DEFERRED ROLLBACK, TEMPORARY, CACHE, LOBSEGMENT and LOBINDEXTABLESPACE_NAMEVARCHAR2(30) Name of the tablespace containing the segmentHEADER_FILENUMBER ID of the file containing the segment headerHEADER_BLOCKNUMBER ID of the block containing the segment headerBYTESNUMBER Size, in bytes, of the segmentBLOCKSNUMBER Size, in Oracle blocks, of the segmentEXTENTSNUMBER Number of extents allocated to the segmentINITIAL_EXTENTNUMBER Size in bytes requested for the initial extent of the segment at create time. (Oracle rounds the extent size to multiples of 5 blocks if the requested size is greater than 5 blocks.)NEXT_EXTENTNUMBER Size in bytes of the next extent to be allocated to the segmentMIN_EXTENTSNUMBER Minimum number of extents allowed in the segmentMAX_EXTENTSNUMBER Maximum number of extents allowed in the segmentPCT_INCREASENUMBER Percent by which to increase the size of the next extent to be allocatedFREELISTSNUMBER Number of process freelists allocated to this segmentFREELIST_GROUPSNUMBER Number of freelist groups allocated to this segmentRELATIVE_FNONUMBER Relative file number of the segment headerBUFFER_POOLVARCHAR2(7) Default buffer pool for the object

我查看下表:

delete rep_common_stat;

两个数据表里的信息不发生变更

trncate table rep_common_stat;

数据段的信息发生变化,数据表信息不发生变化.

BYTES        65536
BLOCKS    8
EXTENTS   1