Starting a Comparison

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Starting a Comparison

You can start a comparison from the Schema Comparison menu or by clicking the Start Comparison ic_start-db-comparison button in the toolbar of the Schema Comparison window. Alternatively, you can also right-click the title bar of either component and choose Compare items from the context menu. This way, you run a comparison for all mapped items in the database comparison components. DatabaseSpy displays comparison result icons that indicate whether a pair of mapped items is equal or contains differences.

diffs_tables-compared

Please note that there are three different kinds of differences displayed in the above screenshot:

 

tblAnimals and tblMedicalTreatments show a Different ic_different sign on both sides of the comparison and the table names are not highlighted:

diffs_diff-diff-child

This indicates that the table name itself is equal, however, one or more child items are different. Expand the table to learn where the differences occur.

diffs_diff-diff-expanded

tblFeedingSchedules and tblZookeepers show a Different ic_different sign on one side and an Equal ic_equal sign on the other side of the comparison; the table names are not highlighted:

diffs_diff-equal

diffs_equal-diff

This indicates that the tables are equal but there is at least one additional item in the table that shows the Different sign. If you expand this table, these additional items are not mapped and indicated with a question mark ic_missing.

diffs_equal-diff-expanded

dbo.tblVeterinarians and test.tblVets, respectively, show a Different ic_different sign and their table names are highlilghted:

diffs_diff-diff-parent

This indicates that the table names are different but the tables have nevertheless been (manually) mapped. Expand the tables to see if any child items are also different.

diffs_diff-diff-parent-exp

A summary of the comparison result on table level is displayed in the Message window. Click the Toggle Message Window ic_toggle-message button if the Message window is not displayed.

msg_schema-compare

To view the differences in more detail—that is, on item level—you have to examine the comparison results in the components. All items that contain differences are automatically expanded in the components so as to allow for easy identification of differences.

 

 

To compare all mapped items:

Do one of the following:

 

Select the menu option Schema Comparison | Compare items.
Click the Start Comparison ic_start-db-comparison button in the toolbar of the Schema Comparison window.
Right-click the title bar in either comparison component and choose Compare items from the context menu.

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