How does the SQL PLUS command work normally?

The following content mainly introduces the actual use of the SQL plus command. If you are interested in the actual use of the SQL PLUS command, the following articles will provide you with relevant knowledge. The following is a detailed description of the article.

1. Execute an SQL script file

 
 

  
  
SQL>start file_name   
  
  
SQL>@ file_name  
 
 

We can save multiple SQL statements in a text file, so that when you want to execute all the SQL statements in this file, use any of the following SQL PLUS commands, this is similar to batch processing in dos.

2. Edit the current input.

 
 

  
  
SQL>edit  
 
 

3. Run the last SQL statement again.

 
 

  
  
SQL>/  
 
 

4. output the displayed content to the specified file.

 
 

  
  
SQL> SPOOL file_name  
 
 

All content on the screen is included in this file, including the SQL statement you entered.

5. Disable spool output

 
 

  
  
SQL> SPOOL OFF  
 
 

The output content is displayed in the output file only when spool output is disabled.

6. display the structure of a table

 
 

  
  
SQL> desc table_name  
 
 

7. COL command:

It mainly formats the display of columns.

The SQL PLUS command has the following options:

 
 

  
  
COL[UMN] [{ column|expr} [ option ...]]  
 
 

The Option can be the following clause:

 
 

  
  
ALI[AS] alias   
  
  
CLE[AR]   
  
  
FOLD_A[FTER]   
  
  
FOLD_B[EFORE]   
  
  
FOR[MAT] format   
  
  
HEA[DING] text   
  
  
JUS[TIFY] {L[EFT]|C[ENTER]|C[ENTRE]|R[IGHT]}   
  
  
LIKE { expr|alias}   
  
  
NEWL[INE]   
  
  
NEW_V[ALUE] variable   
  
  
NOPRI[NT]|PRI[NT]   
  
  
NUL[L] text   
  
  
OLD_V[ALUE] variable   
  
  
ON|OFF   
  
  
WRA[PPED]|WOR[D_WRAPPED]|TRU[NCATED]  
 
 

1). Change the default Column Title

 
 

  
  
COLUMN column_name HEADING column_heading   
  
  
For example:   
  
  
Sql>select * from dept;   
  
  
DEPTNO DNAME LOC   
  
  
10 ACCOUNTING NEW YORK   
  
  
sql>col LOC heading location   
  
  
sql>select * from dept;   
  
  
DEPTNO DNAME location   
  
  
10 ACCOUNTING NEW YORK  
 
 

2) Change the column NAME to the new column NAME "employee name" and put the new column NAME on two rows:

 
 

  
  
Sql>select * from emp   
  
  
Department name Salary   
  
  
10 aaa 11   
  
  
SQL> COLUMN ENAME HEADING ’Employee|Name’   
  
  
Sql>select * from emp   
  
  
Employee   
  
  
Department name Salary   
  
  
10 aaa 11   
  
  
note: the col heading turn into two lines from one line.  
 
 

3). Change the display length of the column:

 
 

  
  
FOR[MAT] format   
  
  
Sql>select empno,ename,job from emp;   
  
  
EMPNO ENAME JOB   
  
  
7369 SMITH CLERK   
  
  
7499 ALLEN SALESMAN   
  
  
7521 WARD SALESMAN   
  
  
Sql> col ename format a40   
  
  
EMPNO ENAME JOB   
  
  
7369 SMITH CLERK   
  
  
7499 ALLEN SALESMAN   
  
  
7521 WARD SALESMAN  
 
 

The above content is an introduction to the use of SQL PLUS commands.

Article by: http://www.programbbs.com/doc/class10-3.htm