chickadee » sql-de-lite » fetch-value

Fetches and returns only the first value (first column) of the next row, or #f if the row contained no column data. Equivalent to using first-column on the result of a fetch, but does not materialize the entire row.

(query fetch-value
       (sql db "select key from cache"))
; => "foo"

(query fetch-value
       (sql db "select key from cache where key=?") "nosuchkey")
; => #f