CAST(expr AS type) as DataFusion performs it (verified against InfluxDB 3 Core).

INTEGER and INT are Int32, SMALLINT is Int16, TINYINT is Int8 and BIGINT is Int64; a value outside the target's range cannot be cast. Text becomes a number only when the whole string is one ("2.5" is not an integer, and a space around a number spoils it; +7, 007, .5, 5. and 1E3 are numbers, and inf, infinity and nan in any case are the float's specials). A float or a decimal becomes an integer by truncation toward zero, a number or boolean becomes text by rendering (a float as the engine writes it, 5000.0 and never 5.0e3; a decimal with its scale, 2.5000; an infinity inf or -inf, a NaN NaN) and a boolean becomes 0 or 1. Null stays null.

A cast that cannot be performed — text that is not a number, an infinity or a NaN as an integer, a number outside the target's range — fails the query on the engine in one of two ways. Over a column, mid-response: InfluxDB 3 Core closes the connection, which Client.HTTP reports as a transport error, so the double reports the same shape. Over a constant, the optimizer folds it first and fails the query before any row is read, with a 500 whose body names the value (see fold/2).

FLOAT and REAL are Float32, which the double does not model: refused by name. A cast of a timestamp is its nanoseconds, which the double keeps only to the microsecond: refused by name, except into a type too narrow for any recent time, which fails as the engine's cast does.