SQL is a strongly typed language. That is, every data item has an associated data type which determines its behavior and allowed usage.

Values to be inserted into a table are converted to the destination column's data type according to the following steps.

The specific operator that is referenced by an operator expression is determined using the following procedure. Note that this procedure is indirectly affected by the precedence

The specific function that is referenced by a function call is determined using the following procedure. Function

SQL UNION constructs must match up possibly dissimilar types to become a single result set. The resolution algorithm is applied separately to each