Diff databases tool allows comparing two databases.
You can find it in Setup > Database tab > Tools section > Diff Databases link.
It prompts you to select a database to compare current database to (you must have access to a setup mode of the database to be listed) and displays differences found in columns and tables. Tables and columns existing in your database only are highlighted in green, tables and columns missing in your database are highlighted in red. Columns that are present in both databases but differ in settings are highlighted in blue and the differences are displayed next to a column name.
Fig. ‘Diff databases’
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