Move a table between MySQL databases

Having organized a lot of datasets in severeal MySQL databases on the same (local)-server the I needed to move a table to another database. The posted solution is copy-paste from Eric Bergen on the MySQL forum:

Alter table can be used to move tables from one db to another.

alter table old_db.foo rename new_db.foo

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Modify MySQL Tables

After setting up my first small databases the next learning steps concern basic operation on existing tables in a MySQL database, such as deleting or creating additional variables/columns in a table. I found tech-recipes.com very helpful:

Delete a variable/column

To delete the column MyCol from the table MyTable, use the following SQL command:

ALTER TABLE MyTable DROP MyCol

Comment: Tech-Recipes.com used single-quotes around MyCol and MyTable which I found not necessary.

Add a column/variable

To add a column called email […] with a datatype of VARCHAR(60) to the table contacts, use the following SQL statement:

ALTER TABLE contacts ADD email VARCHAR(60);

This first statement will add the email column to the end of the table. To insert the new column after a specific column, such as name, use this statement:

ALTER TABLE contacts ADD email VARCHAR(60) AFTER name;

If you want the new column to be first, use this statement:

ALTER TABLE contacts ADD email VARCHAR(60) FIRST;

Update/Change the values in a column

One would use the UPDATE statement so I looked it up in the reference

UPDATE [LOW_PRIORITY] [IGNORE] table_reference
SET col_name1={expr1|DEFAULT} [, col_name2={expr2|DEFAULT}] ...
[WHERE where_condition]
[ORDER BY ...]
[LIMIT row_count]

In order to update the column intensity in the table measures from “20%” to simply “20” one would
UPDATE measures SET intensity="20" WHERE intensity="20%";