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Analysing your table

AQT offers a number of options to quickly analyse your table. These are available under the Analyse menu option, or Analyse toolbar button. It is possible to customize the toolbar to have individual buttons for each of these functions.

These all work by generating an SQL statement which makes the appropriate query.



Number of rows

Displays the number of rows in your table.

Number of distinct values of column

How many different values the column takes in the table. You must select at least one column first.

  • if the column is unique, the result will equal the number of rows in the table.
  • If however the column is the same for every row, the result will be 1.

This can often be a quick way to understand the characteristics of a column.

Analyse column

You must select at least one column first. This is a more useful version of the previous query. It will show you all the distinct values the column takes, and the number of times each value occurs. This provides a very simple way of quickly seeing the type of data held in a column.

Duplicate values of column

You must select at least one column first. This shows you which column values occur more than once in the table. This is often useful if you have a column which you think should be (mostly) unique – and you want to see which values are not unique.

SQL used by AQT

To see the SQL that AQT uses for these queries, look at the Status Bar of the Data Display window that shows the results. You can then edit this SQL by clicking on File > Edit SQL in SQL window.

Analysing Multiple Columns

The Number of distinct values of column, Analyse Column and Duplicate values of Column functions can be used be used with multiple columns from your table. Use the Ctrl and Shift keys to select multiple columns from your column list then click on the appropriate Analysis button.

You will not be able to do if you have selected Options > Unicode Options > Support unicode characters in table and column names. When this is selected, AQT uses a unicode-enabled listbox for the column for displaying column names. This listbox doesn't allow multiple items to be displayed.