Difference between revisions of "Ora2:Saving and Retrieving Queries"

From mi-linux
Jump to navigationJump to search
Line 101: Line 101:
 
</code>
 
</code>
  
For example, to run the file created previously:
+
For example, to run the personnel file:
  
 
  start personnel  
 
  start personnel  
  
 +
Create a SQL query file called query2, which produces a report on Salesmen earning more than 2500:
  
 +
ed  query2
  
Create a query that lists all the employees in department 20 and save the results in a file called EMP.txt:
+
Then type in the following:
SPOOL EMP.TXT
+
 
SELECT * FROM EMP
+
REM List salespeople who earn more than 2500 per month
  WHERE DEPTNO = 20;
+
SELECT DEPTNO,  ENAME,  SAL  FROM EMP
  SPOOL OFF
+
WHERE JOB  = 'SALESMAN'  AND  SAL + COMM  >  2500;  
 Create a query that lists all the clerks and save the results in a file called CLERKS.txt:
+
 
+
Commments in the code:
 +
* REM at the start of the line indicates a comment
 +
* if the documentation spans several lines, use /* at the start and */ at the end of the comment
 +
 
 +
Save as before and to execute it:
 +
 
 +
start query2
 +
 
 +
== SPOOL and Save ==
 +
 
 +
The SQL query file could include a SPOOL command so that the results of the query can also be saved:
 +
 
 +
ed emplist
 +
 
 +
In the editor type:
 +
 
 +
spool emplist.txt
 +
select * from emp;
 +
spool off
 +
 
 +
Save and exit as before.
  
 +
Create a query that lists all the employees in department 20 and save the results in a file called emp.txt:
 
 
 +
spool emp.txt
 +
select * from emp
 +
where deptno = 20;
 +
spool off
  
+
== Exercise 2.2 ==
  
+
2.2.1 Create a query that lists all the clerks and save the results in a file called clerk.txt. The output should be similar to:
  
 +
<pre style="color: blue">
 
EMPNO ENAME      JOB              MGR HIREDATE        SAL      COMM    DEPTNO
 
EMPNO ENAME      JOB              MGR HIREDATE        SAL      COMM    DEPTNO
 
----- ---------- --------- ---------- --------- ---------- ---------- ----------
 
----- ---------- --------- ---------- --------- ---------- ---------- ----------
Line 127: Line 155:
 
  7900 JAMES      CLERK          7698 03-DEC-81        950                    30
 
  7900 JAMES      CLERK          7698 03-DEC-81        950                    30
 
  7934 MILLER    CLERK          7782 23-JAN-82      1300                    10
 
  7934 MILLER    CLERK          7782 23-JAN-82      1300                    10
The editor can be used to create a file from scratch. To create a command file which produces a report on Salesmen earning more than 2500, start Notepad by typing:
+
</pre>
ed  query2
 
Then type in the following:
 
REM List salespeople who earn more than 2500 per month
 
SELECT  DEPTNO,  ENAME,  SAL  FROM  EMP 
 
WHERE  JOB  =  'SALESMAN'  AND  SAL + COMM  > 2500;
 
REM at the start of the line indicates a comment, alternatively, if the documentation spans several lines, use /* at the start and */ at the end of the comment.
 
Save as before and to execute it:
 
start query2
 
 Use Notepad to create a file called QUERY3, which displays the name, salary and commission of all salesmen.
 
 
  
+
2.2.2 Use the editor to create a file called '''query3''', which displays the name, salary and commission of all salesmen.
  
+
When you type:
 +
  start query3
  
+
the results should be similar to:
  
 +
<pre style="color: blue">
 
EMPNO ENAME      JOB              MGR HIREDATE        SAL      COMM    DEPTNO
 
EMPNO ENAME      JOB              MGR HIREDATE        SAL      COMM    DEPTNO
 
----- ---------- --------- ---------- --------- ---------- ---------- ----------
 
----- ---------- --------- ---------- --------- ---------- ---------- ----------
Line 151: Line 171:
 
  7654 MARTIN    SALESMAN        7698 28-SEP-81      1250      1400        30
 
  7654 MARTIN    SALESMAN        7698 28-SEP-81      1250      1400        30
 
  7844 TURNER    SALESMAN        7698 08-SEP-81      1500          0        30
 
  7844 TURNER    SALESMAN        7698 08-SEP-81      1500          0        30
 
+
</pre>
 
 
== SPOOL and Save ==
 
 
 
The SQL query file could include a SPOOL command so that the results of the query can also be saved:
 
 
 
ed emplist
 
 
 
In the editor type:
 
 
 
spool emplist.txt
 
select * from emp;
 
spool off
 
 
 
Save and exit as before.
 
 
 
 
 
  
 
== Summary of the commands ==
 
== Summary of the commands ==
Line 174: Line 178:
 
* ed creates, or edits, a SQL query file  
 
* ed creates, or edits, a SQL query file  
 
* start runs the query file
 
* start runs the query file
 +
 +
== Next Step ==
 +
 +
Creating a [[Oracle_Getting_Started|login]] file.

Revision as of 15:35, 18 February 2016

Main Page >> Oracle and SQL >> Workbook >> Saving and Retrieving Queries

Saving a query

If you wish to keep a query that you have just typed in:

SAVE filename

saves the query in filename.sql

Note:

  • that this instruction only saves the SQL command and not the associated formatting commands (such as headers or footers). To save both SQL and format commands you have to use the editor.
  • You do not need to include the .sql file extension, this will be added automatically.

For example, type in the following to create and save a query file:

select * from emp;
save empquery

It should save the query to a file called empquery.sql in your Documents folder (u:\ drive) by default. You can save the file somewhere else, such as a memory stick, or to a subdirectory.

Assuming you have a memory stick and it is mapped to the e: drive, type the following:

select * from dept;
save e:\deptquery

Or create a folder called oracle in your Documents and save a new query there:

select * from customer;
save u:\oracle\customerquery

It is advisable not to include spaces in your folders or filenames.

Creating a query via the Editor

If you know you want to save a query for future use, for example, to hand-in for your coursework, you can use the default editor to create (or edit) the query.

For example, to create a query file that produces a report on the salaries of employees in department 30:

Create a file
Create a file called personnel (remember, you do not need to include the .sql file extension):
ed personnel
You can also use this method to edit a file previously created.
Editor
This will bring up a Notepad window (Windows) or vi (Linux). Then type in the following:
TTITLE 'ACME WIDGET SALES DEPT PERSONNEL REPORT'
BTITLE 'COMPANY CONFIDENTIAL'
SELECT DEPTNO, ENAME, SAL
FROM EMP
WHERE DEPTNO = 30;
BTITLE OFF
TTITLE OFF

TTITLE and BTITLE are SQL*Plus formatting commands to add header/footers to a report. They need to be switched off at the end; otherwise they will appear with any future queries. Further formatting commands will be introduced later.
Save and exit
Finally save and exit the editor:
File>Save (windows)
File>Exit
or
: wq (Linux)

Note:

  • if using Linux, filenames are case sensitive, so if a file is saved in upper case then it must be retrieved in upper case. The file suffixes that Oracle appends are always in lowercase.
  • You can not access Oracle whilst you are using the editor.

Retrieving and executing a query

The syntax to run a query file is:

START filename

This retrieves the query stored in filename.sql and runs it.

Alternatively the @ symbol can be used instead of start:

@ filename

To just retrieve the query: GET filename

To show the last command typed in: list

For example, to run the personnel file:

start personnel 

Create a SQL query file called query2, which produces a report on Salesmen earning more than 2500:

ed  query2

Then type in the following:

REM List salespeople who earn more than 2500 per month
SELECT  DEPTNO,  ENAME,  SAL  FROM  EMP  
WHERE  JOB  =  'SALESMAN'  AND  SAL + COMM  >  2500; 

Commments in the code:

  • REM at the start of the line indicates a comment
  • if the documentation spans several lines, use /* at the start and */ at the end of the comment

Save as before and to execute it:

start query2

SPOOL and Save

The SQL query file could include a SPOOL command so that the results of the query can also be saved:

ed emplist

In the editor type:

spool emplist.txt
select * from emp;
spool off

Save and exit as before.

Create a query that lists all the employees in department 20 and save the results in a file called emp.txt:

spool emp.txt
select * from emp
where deptno = 20;
spool off

Exercise 2.2

2.2.1 Create a query that lists all the clerks and save the results in a file called clerk.txt. The output should be similar to:

EMPNO ENAME      JOB              MGR HIREDATE         SAL       COMM     DEPTNO
----- ---------- --------- ---------- --------- ---------- ---------- ----------
 7876 ADAMS      CLERK           7788 12-JAN-83       1100                    20
 7369 SMITH      CLERK           7902 17-DEC-80        800                    20
 7900 JAMES      CLERK           7698 03-DEC-81        950                    30
 7934 MILLER     CLERK           7782 23-JAN-82       1300                    10

2.2.2 Use the editor to create a file called query3, which displays the name, salary and commission of all salesmen.

When you type:

 start query3

the results should be similar to:

EMPNO ENAME      JOB              MGR HIREDATE         SAL       COMM     DEPTNO
----- ---------- --------- ---------- --------- ---------- ---------- ----------
 7499 ALLEN      SALESMAN        7698 20-FEB-81       1600        300         30
 7521 WARD       SALESMAN        7698 22-FEB-81       1250        500         30
 7654 MARTIN     SALESMAN        7698 28-SEP-81       1250       1400         30
 7844 TURNER     SALESMAN        7698 08-SEP-81       1500          0         30

Summary of the commands

  • SPOOL saves the results of a query
  • ed creates, or edits, a SQL query file
  • start runs the query file

Next Step

Creating a login file.