连接 ORACLE多表连接分为三大类:NEXT LOOP、SORT MERGE、HASH JOIN。 每一类又分为三小类,有传统连接,Semi Join, Anti Join。(后两种叫做半连接) NEST LOOP方式: 有两个表,驱动表Driving Table,被驱动表Driven Table。 驱动表做一次遍历,被驱动表做多次遍历。 返回第一条记录速度很快
缩小表 initial 空间 (dba 用户执行) 代码语言:javascript 代码运行次数:0 运行 AI代码解释 select'ALTER TABLE '||owner||'.'||table_name||' MOVE TABLESPACE '||tablespace_name||' STORAGE(INITIAL 64K NEXT 32K);'from dba_tables where owner='DSP2'and initial_extent>65536 执行结果: 注意where own...
SQL> create table EYGLE 2 (ID NUMBER(8), 3 UNAME CHAR(1000) ) 4 tablespace eygle 5 pctfree 50 6 initrans 1 7 maxtrans 255 8 ; 表已创建。 SQL> begin 2 for i in 1 .. 100 loop 3 for i in 1 .. 100000 loop 4 insert into eygle values(i,'eygle'); 5 end loop; 6 commit;...
go to next; --使用go to跳出for循环 end; end if; end; end if; end LOOP; <<continue>> average := total / 5; update student t set t.total=total and t.average = average where t.stdId = stdId; end LOOP; end; end autocomputer; --取得学生评论信息的存储过程 create or replace proc...
Kies voor nauwkeurige en functionele productconfiguraties en houd uw focus op de klant. Ingebouwde intelligentie zorgt voor een optimale productmix, zelfs als het product in de loop der tijd verandert. Met begeleide trajecten kan uw verkoopteam binnen enkele seconden deals sluiten door na...
Reduce the time it takes to get the right products and services to market while improving quality and customer satisfaction. Create a closed-loop innovation cycle that integrates quality data, user feedback, and IoT-enabled product usage analysis with a digital thread. ...
NEXT_DAY(d,char):该函数用于返回指定日期后的第一个工作日(由char指定)所对应的日期。 004Oracle中转换函数有哪些? TO_CHAR(data[,fmt[,nls_param]]) :该函数用于将日期值转变为字符串,其中fmt用于指定日期格式,nls_param用于指定nls参数。 TO_CHAR(n[,fmt[,nls_param]]):用于将数字值转换为VARCHAR2数据...
CX - Opportunity Revenue Line Shows trends of Weighted Pipeline CX - Opportunity Revenue Line based on snapshot period and also a projection over the next 3 months. Shows key metrics related to Won Sales such as Won Opportunity Line Revenue and Number of Won Opportunity Revenue Lines, Win ...
for i in 1 .. apex_json.get_count('groups') loop apex_string.push ( p_table => l_group_names, p_value => apex_json.get_varchar2 ( p_path => 'groups[%d].name', p0 => i )); end loop; -- -- save group names in session ...
next()) { for (int j = 1; j <= col_cnt; j++) { o = rs.getObject(j); } } 调整后的代码实际执行时间为3.156秒 从测试结果可以看出性能提高了1倍多,如果采用分页模式数据库每次还需发生磁盘IO的话那性能可以提高更多。 iBatis等持久层框架考虑到会有这种需求,所以也有相应的解决方案,在iBatis里...