create table進階學習系列(八)

wisdomone1發表於2013-01-22
create table進階學習系列(八)
  繼續學習create table table_properties子句
語法:
SQL> select cache from user_tables where table_name='T_PROP';
CACHE
----------------------------------------
    N
SQL> drop table t_prop purge;
Table dropped.
SQL> create table t_prop(a int) cache;
Table created.
SQL> select cache from user_tables where table_name='T_PROP';
CACHE
----------------------------------------
    Y
 
----parallel選項的值=cpu個數*parallel_thread_per_cpu,一般不用配置此值,由oracle自動計算得到 
PARALLEL  Specify PARALLEL if you want Oracle to select a degree of parallelism equal to the number of CPUs
available on all participating instances times the value of the PARALLEL_THREADS_PER_CPU initialization parameter.
    
SQL> create table t_prop(a int);
Table created.
SQL> select degree from user_tables where table_name='T_PROP';
DEGREE
----------------------------------------------------------------
         1
SQL> drop table t_prop purge;
Table dropped.
SQL> create table t_prop(a int) parallel 3;
Table created.
SQL> select degree from user_tables where table_name='T_PROP';
DEGREE
----------------------------------------------------------------
         3
        

SQL> create table t_prop(a int);
Table created.
SQL> select dependencies from user_tables where table_name='T_PROP';
DEPENDENCIES
----------------
DISABLED
SQL> drop table t_prop purge;
Table dropped.
---rowdependences用於高階複製環境,increases the size of each row by 6 bytes
SQL> create table t_prop(a int) rowdependencies;
Table created.
SQL> select dependencies from user_tables where table_name='T_PROP';
DEPENDENCIES
----------------
ENABLED        
   
語義:
測試:
後記: 
 

來自 “ ITPUB部落格 ” ，連結：http://blog.itpub.net/9240380/viewspace-753075/，如需轉載，請註明出處，否則將追究法律責任。

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