再试下的博客

Oracle sql 实现查询时将一个字符串按照","逗号分隔，返回分隔后的各个值SELECT DISTINCT REGEXP_SUBSTR ('A-1,B-2,C-3,D-4','[^,]+',1,LEVEL) as "result"FROM DUALCONNECT BY REGEXP_SUBSTR ('A-1,B-2,C-3,D-4','[^,]+',1,LEVEL) IS NOT NULLorder by 1...

1-查询基础2-单行函数3-分组函数-4-多表查询5-子查询6-高级查询7-数据类型8-改变表结构1-查询基础2-单行函数3-分组函数-4-多表查询5-子查询6-高级查询7-数据类型8-改变表结构

https://www.yiibai.com/plsql/declarebegin<executable command(s)>exceptionend;----‘hello world’ 示例:declaremessage varchar2(20):= ‘hello, world!’;begindbms_output.put_line(message);end;/pl/sql分隔符分隔符是一个具有特殊意义的符号。以下是在pl/sql分隔符的列表：分隔符

1、说明：创建数据库create database database-namedrop database dbnamea：alter table tabname add column col typeb：alter table tabname drop column colnamealter table tabname add primary key(col)alter table tabname drop primary key(col)create [unique] index idxna

<select id="queryProductCount" parameterType="com.want.common.pojo.Pagination" resultType="java.lang.Long"> SELECT count(*) FROM SALES.PRODUCT LEFT JOIN SALES.PRODUCT_LEVEL ON PRODUCT_LEVEL.ID = PRODUCT.LV_5_ID WHERE 1 = 1 </select&

–1-- 变动原来列位置alter table t rename column old_name to temp_namealter table t add (old_name varchar2(50));update t set old_name =temp_name;alter table t drop temp_name;—2---不变原来字段位置alter table t add (temp_name varchar2(50));update t set temp_name=o

dbms_random.valueselect dbms_random.value from dual; ---[0,1)select dbms_random.value(1,10) from dual; ---[1,10)dbms_random.normalselect dbms_random.normal from dual; ---1.0748正态分布的随机数，此正态分布标准偏差为1，期望值为0。 68%介于-1与+1之间， 95%介于-2与+2之间， 99%介于-3与+