Sometimes a table has all the fields you need and sometimes it doesn’t. I sometimes need to create flag fields or summary fields to hold additional information. So here are the methods I use.
Add a 1 char flag field
select *, ' ' as myflag from table...
Add a column with more than one character or a data type
select *, cast('' as varchar(10)) as mytextfield, cast('' as datetime) as mydatefield from table...
Add several columns using alter
Select * into #mytemptable from table...
Alter table #mytemptable
Add ( col1 varchar(10) null,
col2 datetime null,
col3 int null,
col4 char(1) null
)
Summary field
select units, price, unitsxprice as extended price from table...
Concatenated field
select firstname+" "+lastname as name from table...
Syntax may vary slightly depending on database.
