# Merge Join

{% hint style="warning" %}
**Workshop - Merge Join**

A workshop to illustrate various SQL joins.

In this workshop, we're going to run through the various join types available in the Merge join step.
{% endhint %}

{% embed url="<https://www.loom.com/share/cdbbff783c7549e09cf9fddef5ccefde>" %}

***

{% hint style="info" %}
**Create a new Transformation**

Any one of these actions opens a new Transformation tab for you to begin designing your transformation.

* By clicking File > New > Transformation
* By using the CTRL-N hot key
  {% endhint %}

<figure><img src="/files/dgHWlaPxq9BeHE4bFoXn" alt="" width="375"><figcaption><p>Merge Join</p></figcaption></figure>

{% tabs %}
{% tab title="1. Data Grid" %}
{% hint style="info" %}
**Data grid**

The Data grid step allows you to enter a static list of rows in a grid. This is usually done for testing, reference or demo purposes.

Options

* Meta tab: You can specify the field metadata (output specification) of the data
* Data tab: This grid contains the data. Everything is entered in String format so make sure you use the correct format masks in the metadata tab.
  {% endhint %}

1. Drag the Data Grid step onto the canvas.
2. Open the Data Grid properties dialog box.
3. Ensure the following details are configured, as outlined below:

<div align="left"><figure><img src="/files/nXZbbLNpCsFBPVbaz5ib" alt=""><figcaption><p>ABCD - Data Grid</p></figcaption></figure> <figure><img src="/files/5h0mHmmKTNOQMoM8rYxo" alt=""><figcaption><p>Red Blue Yellow - data grid</p></figcaption></figure></div>
{% endtab %}

{% tab title="2. Merge Join" %}
{% hint style="info" %}
**Merge Join**

The Merge Join step performs a classic merge join between data sets with data coming from two different input steps. Join options include INNER, LEFT OUTER, RIGHT OUTER, and FULL OUTER.
{% endhint %}

1. Drag the Merge Join step onto the canvas.
2. Open the Merge Join properties dialog box.
3. Select various Join Types to view the resulting dataset

<figure><img src="/files/xvgn45La24cNjvq0mqex" alt="" width="375"><figcaption><p>Merge Join</p></figcaption></figure>

{% hint style="warning" %}
Obviously you need to join on a unique key(s)
{% endhint %}
{% endtab %}

{% tab title="3. RUN" %}

1. Click the Run button in the Canvas Toolbar.
2. Click on the Dummy step Preview tab:

**INNER Join**

<figure><img src="/files/JLWjg6Mzj00L9mAGcQru" alt=""><figcaption><p>INNER Join</p></figcaption></figure>

**LEFT OUTER Join**

<figure><img src="/files/2xYxox7DsedbQ0xUiTfa" alt=""><figcaption><p>LEFT OUTER Join</p></figcaption></figure>

**RIGHT OUTER Join**

<figure><img src="/files/sgFXkfYOdmGMpW2YUZuB" alt=""><figcaption><p>RIGHT OUTER Join</p></figcaption></figure>

**FULL OUTER Join**

<figure><img src="/files/kyFju85hBemtlZ0Fa0nu" alt=""><figcaption><p>FULL OUTER Join</p></figcaption></figure>

{% hint style="info" %}
Now give it a go with the 'Merge Streams' scenario ..
{% endhint %}
{% endtab %}
{% endtabs %}


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