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Deleting duplicate records and retaining map objects in MapInfo Pro

Products affected: MapInfo Pro™
When users encounter a mappable table with duplicate records, there is a tool called "Delete Duplicates" found in MapInfo Pro that can delete these duplicate records and retain map objects.

Here is the original table:
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The Delete Duplicates tool deletes duplicate records from a table while retaining map objects. This tool does not change the original table in any way. Keep in mind that MapInfo Pro has a 255 byte/ 5-column limit for a Group by clause, so the size of your columns may need to be edited if they are unusually wide.
Duplicate rows means rows that have duplicate occurrences of the same column value for the column selected.
Removing Duplicate Records from a Table
Before opening the Delete Duplicates tool in MapInfo Pro, make sure the tables being edited are open.
To remove duplicate records from a table and save the cleaned table to a new file:
  1. Open the table or tables with duplicates records.
  2. On the HOME tab, in the Tools group, click Tool Extensions, and double-click Delete Duplicates on the Running tab.
The Delete Duplicate Records dialog box opens. The list of tables on the left contains all of the currently open tables.
  1. Select the table with duplicates to be deleted from the first column. A list of the columns in that table displays on the right.
  2. Select the column that contains information that should be unique to each row from the Select Columns list.
CAUTION:
To avoid deleting data incorrectly, give this step a lot of thought. For example, it is not recommended to select customer names or addresses for this step.
  1. Select the Count check box to add a column to the new table that shows the number of instances of the column value found in the original table. This is an optional feature.
  2. Click OK. The “Please Choose a Path” dialog box displays.
  3. Select a path and a file name for the new table in this dialog box. Then select Save. The tool removes rows containing duplicate column values according to the column selected. A Browser window displays with the results of the new table.
The last column contains the count of instances of the row containing duplicate column values in the original table.
 
Here the tool is launched and the table and field to use for the "Group by" is highlighted and the optional "count" checkbox is checked, to return the number of duplicate records encountered:
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Here the new table is given a name and location where it is to be written:

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Here is the new table - note that the "Count" column is called "_col12" as "count" is a reserved word and that there are 3 duplicate records in the original table - rename the Count column if desired.

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UPDATED:  May 21, 2019