Read MySQL result from shell script - mysql

Question

at first, I am a very new on shell scripting, so please don't shoot me !! :)
What I try to do. I have a multi-site WordPress installation, and I like to write a script that will be able to export specific tables from the schema either by passing the site id as argument in shell script, or by set an option to export all selected the tables of the schema.
The WordPress, in order to recognize which table set is for which site, changes the prefix of each table set. So In example does the following :
wp_options
wp_1_options
...
wp_x_options
In addition, the WordPress store the blog id in a special table called wp_blogs
So, from my shell script I run the following code :
mysql -uUSER -pPASS -e 'SELECT `blog_id` AS `ID`, `path` AS `Slug` FROM `wp`.`wp_blogs`'
and I am getting the following results
+----+---------------------------+
| ID | Slug |
+----+---------------------------+
| 1 | / |
| 2 | /site-2-slug/ |
| 4 | /site-4-slug/ |
| 5 | /site-5-slug/ |
| 6 | /site-6-slug/ |
| 7 | /site-7-slug/ |
| 8 | /site-8-slug/ |
| 9 | /site-9-slug/ |
| 10 | /site-10-slug/ |
+----+---------------------------+
So, now the actual question is, how can I parse the MySql result line by line, in order to get the ID and the Slug information ?
Side note 1 : The whole script has been generated and run's somehow manually. I need now this information in order to automate even farther the exporting script.
*Side note 2 : The MySql executed via the Vagrant ssh like the following line : *
sudo vagrant ssh --command "mysql -uroot -proot -e 'SELECT blog_id FROM wp.wp_blogs'"

Answer 1

You could save the result in a file using INTO like below:
SELECT blog_id, path FROM wp.wp_blogs
INTO OUTFILE '/tmp/blogs.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n'
And then you could process it line by line either usingsed/awk/simple while loop. Say you want to search for site and replace it with mysite, you could do something like:
awk -F',' '{print "Id: " $1 ", path: "$2}' /tmp/blogs.csv ##or simply cat the file.