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MapInfo Monday: Save Table As Older Version

  • 1.  MapInfo Monday: Save Table As Older Version

    Employee
    Posted 2 hours ago

    From time to time, we get a question like this:

    "How can I save a TAB file into a lower version so that the third-party company I work with can load the table into, say, MapInfo Pro v15.0?"

    TAB File Version

    As part of the header information in a MapInfo TAB file you will find a version number. You can see this by opening the TAB file in a text editor.

    Here you see the metadata for an extended TAB file. Notice that it states version 1520 on the second line. This means that you will need MapInfo Pro v15.2 or newer to open this table.

    image
    And there is the metadata for a classic TAB file. Here it states version 300. In this case, only MapInfo Pro v3.0 is required.
    image
    Typically, a MapInfo TAB file starts its life as a plain version 300 table. Then you start using the file, adding records to it and the version can change over time. MapInfo Pro keeps track of what version is required for certain things. This could be the column type, the projection, and the object types saved to the table.
    The version can only change to a higher version. MapInfo Pro never lowers the version.
    There can be many reasons why MapInfo Pro bumps up the version of a table. In the example above, the difference lies in the move from a classic TAB file to the extended TAB file. The extended TAB file, that supports a near-unlimited amount of data, requires MapInfo Pro v15.2 or newer. You can't open this table in older versions.
    The chapter File Versions and TAB, MIF/MID, and WOR Support is a good source of information about features implemented in specific versions of MapInfo Pro and the minimum version required.

    Saving Table into Lowest Possible Version

    Normally, when you create a copy of a table, it will save the content into a table of the same version.
    There is, however, a workaround to save the content of a table into the lowest possible version. You can't control exactly what version this will result in because that depends on various things in and around the table, as we discussed above.
    You can however try this:
    1. Create a new table where you base the new table on the existing table.
    image
    2. Make sure you keep the columns from the existing table in the new table and only check Support M/Z if you need it.
    image
    3. Select the classic MapInfo Table (MapInfo (*.tab)) instead of the MapInfo Extended Table (MapInfo Extended (*.tab)).
    This will of course not work if your extended table holds more data then a classic table can hold.
    image
    The version of this new table will be 300. That means it can be opened almost in almost any version of MapInfo Pro.
    OK, in my case the version is 300. If you are using a newer projection, the version may be higher. This depends on when MapInfo Pro began supporting the building blocks of the projection. That is the Datum, the Projection Type and so on.
    Now that you have created this new empty table, you can insert the records from the existing table into it. From the Table tab, select Append Rows from the Edit group.
    Now select to append all rows from the existing table to the new classic table.
    image
    When the rows have been inserted, save the changes to the table.
    As MapInfo Pro adds the rows from the existing table, it will change the version of the new table based on what is needed.
    When I had inserted all the rows and saved the table, the version of the table had changed from version 300 to version 950.
    I hope this helps.


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    Peter Horsbøll Møller
    Principal Presales Consultant | Distinguished Engineer
    Precisely | Trust in Data
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