can I use a variable to specify OUTFILE in mysql

Question

Is there a way to do something like the following ? which doesn\'t work but shows what I want to do

SET @OutputPath = \'/Users/jo/Documents\'
SET @fullOutput         


        

Answer 1

Edit: Saving data(e.g. a table) into file without using variable (only constant values)

-- folder_path could could be like => c:/users/sami
-- choose the directory/folder already available in system
-- and make sure you have access to write the file there

SELECT * INTO OUTFILE 'folder_path/filename.csv'
FIELDS TERMINATED BY ',' 
OPTIONALLY ENCLOSED BY '"'
FROM database.tableName;

Now using variable

Whenever you have to use a variable name in sql, you need dynamic sql (which is applicable in stored procedures only, neither in simple sql query nor in triggers or functions)

SET @OutputPath := 'Users/jo/Documents'; //or any folder_path
SET @fullOutputPath := CONCAT(@OutputPath,'/','filename.csv');
SET @fullOutputPath2 := CONCAT(@OutputPath,'/','filename2.csv');

set @q1 := concat("SELECT * INTO OUTFILE ",@fullOutputPath,
" FIELDS TERMINATED BY ',' 
OPTIONALLY ENCLOSED BY '\"'
FROM database.tableName");

set @q2 := concat("SELECT * INTO OUTFILE ",@fullOutputPath2,
" FIELDS TERMINATED BY ',' 
OPTIONALLY ENCLOSED BY '\"'
FROM database.tableName2");

prepare s1 from @q1;
execute s1;deallocate prepare s1;

prepare s1 from @q2;
execute s1;deallocate prepare s1;

As you had both ' and " in your query already, so I concatenated your query using " and used \ to escape your original " to ensure its use as a literal character and not used for concatenation

I just told the use of variable in sql. First You should make sure if your query works like example at the top (without using variable)

Conclusion: If your above query works fine then my told dynamic sql will work as well given that you are using it in some stored procedure.