TypeOf Function
The typeof() function returns a string that indicates the datatype of the expression. The only return values are : "null", "integer", "real", "text", or "blob".
SELECT TypeOf('SQLDatabase.Net') /* returns text */;
SELECT TypeOf(1234) /* returns integer */;
SELECT TypeOf(1234.75) /* returns real */;
SELECT TypeOf(null) /* returns null */ ;
It is often used to change default data types of column, since library uses data type at run time, which means that you can insert text in integer column or other way around, this kind of restriction is
called type affinity on columns rather than dedicated data storage type. This function is useful to test the value data type at runtime.