How to properly assign null value from bash script to mysql?

by edmond_brakus , in category: MySQL , 13 days ago

How to properly assign null value from bash script to mysql?

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1 answer

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by deron , 10 days ago

@edmond_brakus 

To assign a null value from a bash script to a MySQL database, you need to use the NULL keyword in your SQL query.


Here is an example of how to assign a null value to a specific column in a MySQL table using a bash script:

  1. First, make sure you have the mysql command line client installed. If not, you can install it by running sudo apt-get install mysql-client or using your package manager.
  2. In your bash script, define a variable that holds the value you want to assign or use the keyword NULL directly. For example, if you want to assign a null value to the my_column column, you can define a variable like this:
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value=NULL


Or assign a specific value:

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value="some_value"


  1. Construct your SQL query to insert or update the table, including the assigned value using the $value variable. For example, to insert a new row with a null value assigned to my_column, you can use the following snippet:
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sql="INSERT INTO your_table (my_column) VALUES ($value);"


Or update an existing row:

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sql="UPDATE your_table SET my_column = $value WHERE id = 123;"


  1. Finally, execute the SQL query using the mysql command line client, passing the SQL query as an argument to the -e flag. For example:
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mysql -u username -p password -e "$sql" your_database


Replace username, password, and your_database with your MySQL credentials and database name respectively.


By following these steps, you can successfully assign a null value from a bash script to a MySQL database.