Database Reference
In-Depth Information
EQUALITY where
clause between the two columns in the SQL state-
ment.
Data Type Indicator
indicates the data type of the column, such as
num-
ber
,
character
,
date
, and so on.
Column Name
indicates the column name as defined in the table descrip-
tion.
Column Selector
allows you to individually select or deselect columns
to be included in the SQL statement for processing. This may also in-
clude columns that you want to use in the
where
clause but not display
in the output of the SQL statement. The basic rule is that you need to se-
lect all the columns you want to display, but you don't necessarily have
to display all the columns you select.
As you add and join tables and select columns to operate on, the region at the bot-
tom of the screen begins to change. This region is subdivided into several tabs:
The
Conditions tab
shows one row for each column selected in the area
above and allows you to further define its attributes. (More on this fea-
ture in just a moment.)
The
SQL tab
displays the SQL statement as the wizard builds it. Al-
though it's not directly editable, you can easily highlight the statement
and cut it to the clipboard from here.
The
Results tab
shows the results of running the SQL statement and al-
lows you to download the resulting data in CSV format.
The
Saved SQL tab
allows you to save, recall, and manage statements
that have been built with the Query Builder. There are also filters that let
you search and limit which saved queries display.
All but the Conditions tab are self explanatory, so lets go over this one in a little
more detail.
Figure 2-20
shows an example three-table join with five columns selected
to operate on.
