This falls under “I knew I could do this but I didn’t realize I could apply it this way!”
You can do
SELECT 1 from table1;
Which will return n rows, each row having 1 field whose value is 1. n is the number of rows in table1.
SELECT "string" from table1 works similarly.
However, I never considered using
SELECT "string" as "debug statement" to debug code.
For instance,
mysql> SELECT "SELECT foo from bar where baz>0" as
"debug";;
+---------------------------------+
| debug |
+---------------------------------+
| SELECT foo from bar where baz>0 |
+---------------------------------+
1 row in set (0.00 sec)
Neat trick! This is why I follow the MySQL Users general list, because every so often a gem like this comes up. Plus, I can’t resist helping folks out. And if …
[Read more]