connect by level <= 100000; 上面SQL是利用了Oracle数据库语法的几个实用小技巧实现的: 1、利用Oracle特有的“connect by”树形连接语法生成测试记录,“level <= 10”表示要生成10记录; 2、利用rownum虚拟列生成递增的整数数据;--虚拟出0-100的数值 TRUNC(TO_DATE('24-Nov-1999 08:37 pm','dd-mon-yyyy ...
PLSQL函数学习-Startwith...ConnectBy create table myTestTable as select rownum as id,to_char(sysdate + rownum/24/3600, 'yyyy-mm-dd hh24:mi:ss') as inc_datetime,trunc(dbms_random.value(0, 100)) as random_id,dbms_random.string('x', 20) random_string from dual connect by level <=...
plsql创建表后不能直接让id递增,因此要手动创建,下面是例子: 1.创建表 SQL: create table student( id number primary key, name varchar2(20)not null, age int ); 2.创建一个序列 SQL: CREATE SEQUENCE student_id_seq INCREMENT BY 1 -- 每次加几个 START WITH 1 -- 从1开始计数 NOMAXVALUE -- ...
5 / Table created. SQL> SQL> insert into job (EMPNO, Jobtitle) values (1,'Tester'); 1 row created. SQL> insert into job (EMPNO, Jobtitle) values (2,'Accountant'); 1 row created. SQL> insert into job (EMPNO, Jobtitle) values (3,'Developer'); 1 row created. SQL> insert into...
1.instr函数为字符查找函数,其功能是查找一个字符串在另一个字符串中首次出现的位置。instr函数在Oracle/PLSQL中是返回要截取的字符串在源字符串中的位置。 instr( string1, string2, start_position,nth_appearance ) 参数 ● string1:源字符串,要在此字符串中查找。
postgresql in模糊查询 plsql模糊查询表名 一.简单查询 1.Select 列名,列名..from select e.empno,e.ename,e.job,e.sal from emp e(别名); 2.带条件查询 select 列名,列名,...,列名 from 表名 where --查询名字叫SMITH的员工的信息 select * from emp where ename='SMITH';(字符串类型加单引号)...
下面是建sequence的sql语句和介绍: createsequencezhu_onestartwith1incrementby1maxvalue99999999nocycle; Oracle序列的语法格式为:CREATESEQUENCE序列名 [INCREMENTBYn] [STARTWITHn] [{MAXVALUE/MINVALUEn|NOMAXVALUE}] [{CYCLE|NOCYCLE}] [{CACHEn|NOCACHE}]; ...
startwith50 maxvalue60 minvalue50 cycle cache3; 2) sqlcreatesequencenew_s; sqlinsertintonew(new_id,last_name,first_name) values(new_s.nextval,daur,permit); 三、createview语句 语句:CREATE[ORREPLACE][FORCEINOFORCE]VIEW[schema.]view_name [(alias[,alias]...)] ASsubquery [WITHCHECKOPTION[CO...
PL/SQL example from Chapter 1 DECLARE CURSOR c1 is SELECT ename, empno, sal FROM emp ORDER BY sal DESC; -- start with highest paid employee my_ename VARCHAR2(10); my_empno NUMBER(4); my_sal NUMBER(7,2); BEGIN OPEN c1; FOR i IN 1..5 LOOP FETCH c1 INTO my_ename, my_empno,...
oracle里面是没有自增长这个概念的，如果真要实现自增长，可以用sequence来实现