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Transcripts for the above video clip:
Pivot Tables 2007 Data base set up
Before you can
create a Pivot Table in Excel you need to understand the format
that Excel likes
the data to come in.
So here we have a
simple data base related to sales people
and some products sold. A couple of things you need to
realize.
The first thing is
that Pivot Tables require that every single column has a label in
it. So you’ll see for example that here we don’t have a label
and if you try set up a Pivot Table it will explain that there is a
problem with this – you either need to delete these columns or
else what I like to do
is just give it a label and in this case I am going to call it
“blank” and if you had another column you would call it Blank 1,
Blank 2 etc, because at some stage you may actually need these extra
columns.
The second thing to
understand is that the column labels have to be unique. Excel is
going to use these to decide what type of reports it will create so
having two columns called Product like this one here and this one
here will cause a problem and a Pivot Table won’t be created. So
we need to make sure that they are all unique so I am going to go
here and change the name
to be Sales.
Another thing about
the column headings is that the Pivot Table cannot have a merged
cell - so you can see
here I have got the dates description but it is merged and applies
to those two columns. You cannot have that so you need to unmerge
the cells and now we have this other problem – a column without a
header which we need to fix. In
this case and I am going to take these down because these two
provide the correct label.
Also it is important
that your labels are descriptive so you’ll see here just having
date 1 or date 2 would be problematic. Here we can see we have got
an order date and a delivery date.
With the nature of
Pivot Tables and what they do which is take a whole chunk of
information and do various sorting and categorizing on them, it is
unnecessary to have these sub- totals built into a report. The pivot
table will do all of this on its own so the data base must come
without the sub- totals. So in this case I am going to go and delete
all of these.
The pivot table also
has some special functionality built in to handle dates. But before
it can use this functionality it needs to recognize the data as a
date – so if you look here you’ll see that
the order date is represented as a number ( 2009 09 25) but
Excel is not recognizing that as a date. So you need to convert this
somehow to be in a date format that Excel recognizes.
Another requirement
of Pivot Tables is that each line must contain all the information
relating to that line. So, for example here, as a human, I can
assume that these two headers apply all the way to here. However
Excel does not assume it and it actually needs to be able to include
there, London and Ben (the city and salesperson) so that when it
does its sorting and categorization and summarization it knows what
information applies to it. So ideally we should not have blanks in
any of the columns – they should have information that describes
the entire row of information.
So for our Pivot
Table to work your data cannot really look like that - it should
look like this. You’ll notice that every column has got a header,
the headers are all descriptive, they are all unique, there are no
blanks (all these numbers have been filled in), the dates are
now represented as a date (are recognized as a date), there
are no merged cells and
all sub-totals have been removed
Once you are in this
format you can get onto actually building the Pivot Table.
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