Difference between revisions of "Ora2:Saving and Retrieving Queries"
(→Linux) |
(→Linux) |
||
Line 39: | Line 39: | ||
For example, instead of: | For example, instead of: | ||
+ | |||
save u:\filename | save u:\filename | ||
Type: | Type: | ||
+ | |||
save filename | save filename | ||
Revision as of 15:53, 1 October 2019
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 u:\filename
saves the query in filename.sql in your Documents folder (u:\ drive) by default.
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 u:\empquery
It should save the query to a file called empquery.sql in your Documents folder. 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
First, go to your Documents library and create a folder called oracle in the top directory (you do not need to exit Oracle to do this). Then return to Oracle and type the following:
select * from customer; save u:\oracle\customerquery
It is advisable not to include spaces in your folders or filenames.
Linux
The filenames given on this page include the directory name, e.g., u:\. If you are using Oracle from a Linux client, such as mi-linux, then you do not need to include this, just the filename.
For example, instead of:
save u:\filename
Type:
save filename
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.
Follow these steps to create a SQL 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 u:\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 if you are using vi on Linux
: 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.
- on Linux do not use the directory names, that is, u:\
- 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 u:\filename
This retrieves the query stored in filename.sql and runs it.
For example, to run the personnel file:
start u:\personnel
Alternatively the @ symbol can be used instead of start:
@ u:\empquery
To just retrieve the query:
GET u:\filename
To show the last command typed in:
list
Further examples
To create a SQL query file called query2, which produces a report on Salesmen earning more than 2500:
ed u:\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 u:\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. Then run it:
start emplist
Create a query file called emp20.sql that lists all the employees in department 20 and save the results in a file called emp.txt:
ed emp20
then add:
spool emp.txt select * from emp where deptno = 20; spool off
Exercise 2.2
2.2.1 What do you need to type to run the emp20.sql file?
2.2.2 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
2.2.3 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:
ENAME SAL COMM ---------- ---------- ---------- ALLEN 1600 300 WARD 1250 500 MARTIN 1250 1400 TURNER 1500 0
Summary of the commands
- SPOOL filename: saves the results of a query
- ED filename: creates, or edits, a SQL query file
- START filename: runs the SQL query file
- @ filename: runs the SQL query file
- LIST: shows the contents of the last query run
- GET filename: shows the contents of a query file (but does not run it)
Next Step
Creating a login file.