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  • Oracle 命令大汇总索引与约束管理

    第四章:索引 
        1.creating function-based indexes 
        sql> create index summit.item_quantity on summit.item(quantity-quantity_shipped); 
        2.create a b-tree index 
        sql> create [unique] index index_name on table_name(column,.. asc/desc) tablespace 
        sql> tablespace_name [pctfree integer] [initrans integer] [maxtrans integer] 
        sql> [logging | nologging] [nosort] storage(initial 200k next 200k pctincrease 0 
        sql> maxextents 50); 
        3.pctfree(index)=(maximum number of rows-initial number of rows)*100/maximum number of rows 
        4.creating reverse key indexes 
        sql> create unique index xay_id on xay(a) reverse pctfree 30 storage(initial 200k 
        sql> next 200k pctincrease 0 maxextents 50) tablespace indx; 
        5.create bitmap index 
        sql> create bitmap index xay_id on xay(a) pctfree 30 storage( initial 200k next 200k 
        sql> pctincrease 0 maxextents 50) tablespace indx; 
        6.change storage parameter of index 
        sql> alter index xay_id storage (next 400k maxextents 100); 
        7.allocating index space 
        sql> alter index xay_id allocate extent(size 200k datafile ''c:/oracle/index.dbf''); 
        8.alter index xay_id deallocate unused; 

        第五章:约束
        1.define constraints as immediate or deferred 
        sql> alter session set constraint[s] = immediate/deferred/default; 
        set constraint[s] constraint_name/all immediate/deferred; 
        2. sql> drop table table_name cascade constraints 
        sql> drop tablespace tablespace_name including contents cascade constraints 
        3. define constraints while create a table 
        sql> create table xay(id number(7) constraint xay_id primary key deferrable 
        sql> using index storage(initial 100k next 100k) tablespace indx); 
        primary key/unique/references table(column)/check 
        4.enable constraints 
        sql> alter table xay enable novalidate constraint xay_id; 
        5.enable constraints 
        sql> alter table xay enable validate constraint xay_id; 
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  • 原文地址:https://www.cnblogs.com/HondaHsu/p/796635.html
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