SQL Server Union And Union All

Some steps to be followed while writing union and union all query.

1. Equal number of columns should be in the queries.
2. Data type should be matched.
3. Order of the column and data type should be same.
4. Order by clause needs to be there at the end of the query.

Equal number of column

Data type should be matched


Order of column should be same and Data type
Conversion fails, when converting the varchar value 'India' to data type int.

Order by clause at the end of query