Oracle type/rowtype/record
RECORD: 记录类型,可以理解为是几列数据的集合,使用的时候注意结果集只能有一行 ,引用时使用.来引用内部元素 declare type v_my_record is record (v_ename emp.ename%type, v_job emp.job%type); v_dname dept.dname%type; v_my v_my_record; --需要先定
RECORD: 记录类型,可以理解为是几列数据的集合,使用的时候注意结果集只能有一行
,引用时使用.来引用内部元素
declare type v_my_record is record
(v_ename emp.ename%type,v_job emp.job%type);
v_dname dept.dname%type;
v_my v_my_record; --需要先定义type 再声明变量
begin
v_dname:=&dname;
select ename,job into v_my
from emp inner join dept
on emp.deptno=dept.deptno
where upper(dept.dname)=upper(v_dname) and rownum=1;
dbms_output.put_line(v_my.v_ename||' '||v_my.v_job);
exception when no_data_found then
dbms_output.put_line('nononono..');
end;
ROWTYPE:可以理解为是几列数据的集合,可以对表、视图使用,应用的时候使用 "." 和record类似:
create or replace view v_emp
as
select ename,dname,empno
from emp,dept
where emp.deptno=dept.deptno;
--使用视图%rowtype
declare
v_row v_emp%rowtype;
v_empno emp.empno%type;
begin
v_empno := &请输入编号;
select * into v_row from v_emp where empno= v_empno;
dbms_output.put_line(v_row.ename||','||v_row.dname);
end;

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

AI Hentai Generator
Generate AI Hentai for free.

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



To query the Oracle tablespace size, follow the following steps: Determine the tablespace name by running the query: SELECT tablespace_name FROM dba_tablespaces; Query the tablespace size by running the query: SELECT sum(bytes) AS total_size, sum(bytes_free) AS available_space, sum(bytes) - sum(bytes_free) AS used_space FROM dba_data_files WHERE tablespace_

Creating an Oracle table involves the following steps: Use the CREATE TABLE syntax to specify table names, column names, data types, constraints, and default values. The table name should be concise and descriptive, and should not exceed 30 characters. The column name should be descriptive, and the data type specifies the data type stored in the column. The NOT NULL constraint ensures that null values are not allowed in the column, and the DEFAULT clause specifies the default values for the column. PRIMARY KEY Constraints to identify the unique record of the table. FOREIGN KEY constraint specifies that the column in the table refers to the primary key in another table. See the creation of the sample table students, which contains primary keys, unique constraints, and default values.

Data import method: 1. Use the SQLLoader utility: prepare data files, create control files, and run SQLLoader; 2. Use the IMP/EXP tool: export data, import data. Tip: 1. Recommended SQL*Loader for big data sets; 2. The target table should exist and the column definition matches; 3. After importing, data integrity needs to be verified.

Oracle View Encryption allows you to encrypt data in the view, thereby enhancing the security of sensitive information. The steps include: 1) creating the master encryption key (MEk); 2) creating an encrypted view, specifying the view and MEk to be encrypted; 3) authorizing users to access the encrypted view. How encrypted views work: When a user querys for an encrypted view, Oracle uses MEk to decrypt data, ensuring that only authorized users can access readable data.

There are three ways to view instance names in Oracle: use the "sqlplus" and "select instance_name from v$instance;" commands on the command line. Use the "show instance_name;" command in SQL*Plus. Check environment variables (ORACLE_SID on Linux) through the operating system's Task Manager, Oracle Enterprise Manager, or through the operating system.

Uninstall method for Oracle installation failure: Close Oracle service, delete Oracle program files and registry keys, uninstall Oracle environment variables, and restart the computer. If the uninstall fails, you can uninstall manually using the Oracle Universal Uninstall Tool.

There are the following methods to get time in Oracle: CURRENT_TIMESTAMP: Returns the current system time, accurate to seconds. SYSTIMESTAMP: More accurate than CURRENT_TIMESTAMP, to nanoseconds. SYSDATE: Returns the current system date, excluding the time part. TO_CHAR(SYSDATE, 'YYY-MM-DD HH24:MI:SS'): Converts the current system date and time to a specific format. EXTRACT: Extracts a specific part from a time value, such as a year, month, or hour.

An AWR report is a report that displays database performance and activity snapshots. The interpretation steps include: identifying the date and time of the activity snapshot. View an overview of activities and resource consumption. Analyze session activities to find session types, resource consumption, and waiting events. Find potential performance bottlenecks such as slow SQL statements, resource contention, and I/O issues. View waiting events, identify and resolve them for performance. Analyze latch and memory usage patterns to identify memory issues that are causing performance issues.
