How to Save Oracle SQL Query Output to a File in Proper Format

Understanding Oracle SQL Query Output and Saving it to a File in Proper Format

As a developer, working with databases and shell scripts is a common task. One of the challenges you might face is saving the output of an SQL query from a database (in this case, an Oracle database) to a file in a format that’s easily readable by other applications or tools.

In this blog post, we’ll explore how to save Oracle SQL query output to a file in a tabular format using shell scripts and setting various options to achieve the desired formatting. We’ll also discuss the differences between saving the data as a .txt file, a .csv file, and how these formats can be used with other applications.

Setting Up Your Shell Script

Before we dive into the specifics of saving Oracle SQL query output to a file, let’s take a look at the basics of setting up your shell script. The following code block shows some essential settings that you’ll need to set in your script:

## Essential Settings

set feedback off
set pages 0
set verify off
set pagesize 0 embedded on
SET COLSEP ","
SET LINESIZE 200
SET UNDERLINE =
set markup on
set termout off
BREAK ON ROW SKIP PAGE

Let’s break down what each of these settings does:

set feedback off: This setting controls whether the Oracle database displays feedback messages during query execution. By setting this to off, we can suppress these messages and only see the actual output.
set pages 0: This setting controls how many rows of data are displayed on each page when using a spool command. A value of 0 means that all rows will be displayed in a single page, making it easier to save the data to a file in a tabular format.
set verify off: This setting controls whether Oracle verifies the accuracy of the output before displaying it. By setting this to off, we can ensure that our script outputs the correct data without interruptions or errors.
set pagesize 0: This setting sets the page size for spooling purposes. A value of 0 means that each row will be displayed on a separate line, making it easier to save the data in a tabular format.
embedded on: When this setting is enabled, Oracle embeds the output into the file without creating an extra layer, which can improve performance and reduce file size.
SET COLSEP ",": This setting sets the column separator for spooling purposes. A comma (,) is often used as a standard delimiter when saving data to a file in a tabular format.

Saving Oracle SQL Query Output to a File

Now that we have our essential settings in place, let’s take a look at how to save Oracle SQL query output to a file using the spool command. Here’s an example of how you might do this:

## Saving Oracle SQL Query Output to a File

-- Define the connection details for your database
ORACLE_SID=your_oracle_sid
username=your_username
password=your_password

-- Create the output file
spool your_output_file.txt

-- Execute the SQL query and display its output
SELECT * FROM your_table;

-- Save any additional data to the same file (e.g., error messages)
BREAK ON ROW SKIP PAGE

-- Close the spool command
spool off

In this example, we first define our connection details for the Oracle database. We then create the output file using the spool command and specify that we want to save the data in a tabular format.

Next, we execute the SQL query and display its output. In this case, we’re simply selecting all rows from a table called your_table. You can replace this with any other query you want to run on your database.

Finally, we use the BREAK ON ROW SKIP PAGE command to save any additional data (e.g., error messages) to the same file as before. This allows us to capture both successful and failed execution results in a single log file.

After executing all of these commands, we close the spool command using spool off, which ensures that the output is written to the file without any further interruptions or errors.

Saving Oracle SQL Query Output as a `.CSV` File

When saving Oracle SQL query output to a file, you often want to specify that the data should be saved in a format that’s easily readable by applications like Excel. One way to achieve this is by saving the data as a .csv (Comma-Separated Values) file.

To do this, you’ll need to modify your script to include a few additional settings:

## Saving Oracle SQL Query Output as a .CSV File

-- Define the connection details for your database
ORACLE_SID=your_oracle_sid
username=your_username
password=your_password

-- Create the output file with a CSV extension
spool your_output_file.csv

-- Execute the SQL query and display its output
SELECT * FROM your_table;

-- Save any additional data to the same file (e.g., error messages)
BREAK ON ROW SKIP PAGE

-- Close the spool command
spool off

By changing the spool command’s extension to .csv, we’re telling Oracle to save the data in a format that uses commas as delimiters. This makes it easy for Excel and other applications to read the file without any issues.

Conclusion

In this blog post, we explored how to save Oracle SQL query output to a file in a tabular format using shell scripts and setting various options. We covered essential settings like set pagesize 0 and embedded on, as well as examples for saving data as both .txt files and .csv files.

By following these steps and modifying your script accordingly, you can save Oracle SQL query output to a file that’s easily readable by other applications and tools.

Last modified on 2024-07-08