oracle 算术运算
Oracle默认安装中,已经创建了一个SCOTT用户,默认密码是:tiger,该用户下有四张表分别是: 雇员表(EMP),部门表(DEPT),工资登记表和奖金表。接下来很多操作都是在该用户下完成的。 Oracle开发中,依然存在算术运算,关系运算,和逻辑运算。 Oracle中
Oracle默认安装中,已经创建了一个SCOTT用户,默认密码是:tiger,该用户下有四张表分别是:
雇员表(EMP),部门表(DEPT),工资登记表和奖金表。接下来很多操作都是在该用户下完成的。
Oracle开发中,依然存在算术运算,关系运算,和逻辑运算。
Oracle中的算术运算符,没有C#中的算术运算符丰富,只有+、-、*、/四个,
其中除号(/)的结果是浮点数。求余运算只能借助函数:MOD(x,y):返回x除以y的余数。
案例3:每名员工年终奖是2000元,请显示基本工资在2000元以上的员工的月工资,年总工资。
代码演示:查询中的算术运算
SQL> SELECT ENAME,SAL,(SAL*12+2000) FROM EMP WHERE SAL>2000; ENAME SAL (SAL*12+2000) JONES 2975 37700 BLAKE 2850 36200 CLARK 2450 31400 SCOTT 3000 38000 KING 5000 62000 FORD 3000 38000

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_

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.

To create a user in Oracle, follow these steps: Create a new user using the CREATE USER statement. Grant the necessary permissions using the GRANT statement. Optional: Use the RESOURCE statement to set the quota. Configure other options such as default roles and temporary tablespaces.

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.

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.
