MySQL metadata function to get projected column type in query? Is it possible to get the field type from a MySQL query, in the same way you can get it from a table with the SHOW COLUMNS command? Such as from a derived table,

SELECT x -- presumedMetaFn(x) -- returns "int"
FROM (
  SELECT 1 AS x
  UNION SELECT 2
) AS t;


Given the above query, is there a function or something that I can use to get the type of x? PostgreSQL makes this available with the System Information Functions pg_typeof

SELECT x, pg_typeof(x)
FROM ( VALUES (1),(2) ) AS t(x);
 x | pg_typeof 
---+-----------
 1 | integer
 2 | integer
(2 rows)


I am not looking for metadata on a table, but from the result of query. With psql on PostgreSQL 11+, this is also possible by running \gdesc after the query.
Within MySQL, you can get this information by creating a temporary table, then using DESCRIBE on that temporary table:

CREATE TEMPORARY TABLE `temp`
SELECT ...
FROM ...
LIMIT 0;

DESCRIBE `temp`;


We cannot just use DESCRIBE on the original table because the column we want to know the type of is a calculated column, not something being directly pulled from a table.  Likewise, we cannot use DESCRIBE directly on the query, because DESCRIBE can only be used on tables.  Creating a temporary table solves both of those problems.