Using user-defined variables in %{sql: } clause?

[George]

I am using FR v2.1.6.


I tried to use clause like `%{sql: SELECT ...}`. But length of SQL-query is so large for using as field of SQL-table.
And I thought that I can create variable like myquery = "SELECT ..." as entry of configuration file,
and to use this as `%{sql:${myquery}}`. But it didn't work. I looked into log:
	[sql]      expand: ${myquery} -> {myquery}
	rlm_sql_postgresql: Status: PGRES_FATAL_ERROR

What's wrong?