oracle中PLSQL语句
1.set autot off 禁止使用autotrace命令 set autot on 这个命令包括exp 和 stat(执行语句、生成explain plan、生成统计信息) set autot trace 不执行sql语句,但(生成explain plan、生成统计信息) set autot trace exp stat 与上句同 set autot trace st
1.set autot off 禁止使用autotrace命令
set autot on 这个命令包括exp 和 stat(执行语句、生成explain plan、生成统计信息)
set autot trace 不执行sql语句,但(生成explain plan、生成统计信息)
set autot trace exp stat 与上句同
set autot trace stat 不执行sql语句,但(生成explain plan)
2.序列Sequence_name.nextval 求出接下来的最高值
Sequence_name.currval 最近一次调用nextval时返回的值
3. 创建以10开始的序列create sequence my_sequence start with 10;
查询序列中接下来的最高值 select my_sequence.nextval from dual;
4. create sequence student_seq;
create table student(n varchar(10));
insert into student values('a'||lpad(student_seq.nextval,9,'0'));
select * from student;
N
----------
a000000002
5. --execute immediate 'set constraints all deferred';
create or replace procedure p is
begin
insert into student values ('a000000004');
insert into student values('a000000005');
insert into student values ('a000000006');
commit;
end p;
6.select * from tab;查看表空间中所有表
7.select * from v$tablespace;查看数据库中的所有表空间
8.
set serveroutput on
即打开oracle自带的输出方法dbms_output。在执行set serveroutput on以后,
使用dbms_output方法可以输出信息,
例如:dbms_output.put_line('This is mine');
1)创建存储过程
SQL> set serveroutput on
SQL> create or replace procedure hello IS
2 begin
3 dbms_output.put_line('hello world');
4 end;
5 /
过程已创建。
2)执行存储过程
SQL> execute hello (或者exec hello)
hello world
PL/SQL 过程已成功完成。
3)删除存储过程
SQL> drop procedure hello
2 ;
过程已删除。
9.SQL*Plus 缓冲区默认大小是20,000字符,最大可以增加到1,000,000字符
SQL> execute dbms_output.enable(1000000);
PL/SQL 过程已成功完成。
将缓冲区的内容保存到文件中
SQL> create or replace procedure hello is
2 begin
3 dbms_output.put_line('hello world,zhang da wang,heihei');
4 end;
过程已创建。
SQL> save hello
已创建 file hello.sql --文件的路径为:F:\oracle\product\10.2.0\db_1\BIN
SQL> @hello.sql
过程已创建。
SQL> exec hello
hello world,zhang da wang,heihei
PL/SQL 过程已成功完成。
10.赋值操作符“:=”
if条件判断表达式IF(a=b)
字符串连接操作符“||”
变量声明区位于IS和BEGIN之间

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

Solutions to Oracle cannot be opened include: 1. Start the database service; 2. Start the listener; 3. Check port conflicts; 4. Set environment variables correctly; 5. Make sure the firewall or antivirus software does not block the connection; 6. Check whether the server is closed; 7. Use RMAN to recover corrupt files; 8. Check whether the TNS service name is correct; 9. Check network connection; 10. Reinstall Oracle software.

The method to solve the Oracle cursor closure problem includes: explicitly closing the cursor using the CLOSE statement. Declare the cursor in the FOR UPDATE clause so that it automatically closes after the scope is ended. Declare the cursor in the USING clause so that it automatically closes when the associated PL/SQL variable is closed. Use exception handling to ensure that the cursor is closed in any exception situation. Use the connection pool to automatically close the cursor. Disable automatic submission and delay cursor closing.

In Oracle, the FOR LOOP loop can create cursors dynamically. The steps are: 1. Define the cursor type; 2. Create the loop; 3. Create the cursor dynamically; 4. Execute the cursor; 5. Close the cursor. Example: A cursor can be created cycle-by-circuit to display the names and salaries of the top 10 employees.

To stop an Oracle database, perform the following steps: 1. Connect to the database; 2. Shutdown immediately; 3. Shutdown abort completely.

Building a Hadoop Distributed File System (HDFS) on a CentOS system requires multiple steps. This article provides a brief configuration guide. 1. Prepare to install JDK in the early stage: Install JavaDevelopmentKit (JDK) on all nodes, and the version must be compatible with Hadoop. The installation package can be downloaded from the Oracle official website. Environment variable configuration: Edit /etc/profile file, set Java and Hadoop environment variables, so that the system can find the installation path of JDK and Hadoop. 2. Security configuration: SSH password-free login to generate SSH key: Use the ssh-keygen command on each node

Oracle is not only a database company, but also a leader in cloud computing and ERP systems. 1. Oracle provides comprehensive solutions from database to cloud services and ERP systems. 2. OracleCloud challenges AWS and Azure, providing IaaS, PaaS and SaaS services. 3. Oracle's ERP systems such as E-BusinessSuite and FusionApplications help enterprises optimize operations.

When Oracle log files are full, the following solutions can be adopted: 1) Clean old log files; 2) Increase the log file size; 3) Increase the log file group; 4) Set up automatic log management; 5) Reinitialize the database. Before implementing any solution, it is recommended to back up the database to prevent data loss.

SQL statements can be created and executed based on runtime input by using Oracle's dynamic SQL. The steps include: preparing an empty string variable to store dynamically generated SQL statements. Use the EXECUTE IMMEDIATE or PREPARE statement to compile and execute dynamic SQL statements. Use bind variable to pass user input or other dynamic values to dynamic SQL. Use EXECUTE IMMEDIATE or EXECUTE to execute dynamic SQL statements.
