.. _sphx_glr_auto_examples_03_joining:

Joining tables with imperfect data
==================================


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  <div id='sg-tag-list' class='sphx-glr-tag-list'></div>


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    <div class="sphx-glr-thumbnails">

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    <div class="sphx-glr-thumbcontainer" tooltip="Here we show how to combine data from different sources, with a vocabulary not well normalized.">

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  .. image:: /auto_examples/03_joining/images/thumb/sphx_glr_0040_fuzzy_joining_thumb.png
    :alt:

  :doc:`/auto_examples/03_joining/0040_fuzzy_joining`

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      <div class="sphx-glr-thumbnail-title">Fuzzy joining dirty tables with the Joiner</div>
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    <div class="sphx-glr-thumbcontainer" tooltip="Real-world datasets often come with misspellings, for instance in manually inputted categorical variables. Such misspellings break data analysis steps that require exact matching, such as a GROUP BY operation.">

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  .. image:: /auto_examples/03_joining/images/thumb/sphx_glr_0050_deduplication_thumb.png
    :alt:

  :doc:`/auto_examples/03_joining/0050_deduplication`

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      <div class="sphx-glr-thumbnail-title">Deduplicating misspelled categories</div>
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    <div class="sphx-glr-thumbcontainer" tooltip="Joining tables may be difficult if one entry on one side does not have an exact match on the other side.">

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  .. image:: /auto_examples/03_joining/images/thumb/sphx_glr_0060_multiple_key_join_thumb.png
    :alt:

  :doc:`/auto_examples/03_joining/0060_multiple_key_join`

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      <div class="sphx-glr-thumbnail-title">Spatial join for flight data: Joining across multiple columns</div>
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    <div class="sphx-glr-thumbcontainer" tooltip="Many problems involve tables whose entities have a one-to-many relationship. To simplify aggregate-then-join operations for machine learning, we can include the |AggJoiner| in our pipeline.">

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  .. image:: /auto_examples/03_joining/images/thumb/sphx_glr_0070_join_aggregation_thumb.png
    :alt:

  :doc:`/auto_examples/03_joining/0070_join_aggregation`

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      <div class="sphx-glr-thumbnail-title">AggJoiner on a credit fraud dataset</div>
    </div>


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    <div class="sphx-glr-thumbcontainer" tooltip="We illustrate the InterpolationJoiner, which is a type of join where values from the second table are inferred with machine-learning, rather than looked up in the table. It is useful when exact matches are not available but we have rows that are close enough to make an educated guess -- in this sense it is a generalization of a fuzzy_join.">

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  .. image:: /auto_examples/03_joining/images/thumb/sphx_glr_0080_interpolation_join_thumb.png
    :alt:

  :doc:`/auto_examples/03_joining/0080_interpolation_join`

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      <div class="sphx-glr-thumbnail-title">Interpolation join: infer missing rows when joining two tables</div>
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.. toctree::
   :hidden:

   /auto_examples/03_joining/0040_fuzzy_joining
   /auto_examples/03_joining/0050_deduplication
   /auto_examples/03_joining/0060_multiple_key_join
   /auto_examples/03_joining/0070_join_aggregation
   /auto_examples/03_joining/0080_interpolation_join