Guide Alteryx pour SQL
Alteryx SQL
L’approche traditionnelle de l’accès aux données et de leur préparation implique parfois des tâches chronophages pour les analystes. Frustrés, certains prennent les choses en main et se lancent dans l’apprentissage de la programmation SQL plutôt que de dépendre de l’IT et des développeurs SQL. L’une des principales difficultés de la programmation SQL, c’est de faire en sorte que le code fonctionne ! La correction automatique n’existe pas en SQL : si vous placez un point ou une virgule au mauvais endroit, l’erreur ne sera pas détectée automatiquement et cela peut faire échouer le script.
Alteryx adopte une approche différente, basée sur les workflows, qui permet de préparer, de fusionner et d’analyser les données de plusieurs sources, y compris les données non structurées. Au lieu de passer votre temps à tester et déboguer le code, vous créez un workflow reproductible qui montre précisément à vos collègues, aux autres analystes, à l’IT et aux décideurs comment vous avez extrait et transformé les données. Le résultat ? Moins de temps passé à coder, et plus de transparence et de cohérence.
We’ve listed some of the most common data-related processes that many analysts code in SQL. Alongside, we show how you could do the same using Alteryx. These examples are meant to help analysts who write SQL code understand how to translate their SQL knowledge into an Alteryx workflow.
Select
SELECT, FROM, WHERE, GROUP BY, HAVING, ORDER BY
In SQL
In Alteryx
To access data in Alteryx, you drag and drop an Input Data Tool onto the canvas, locate the database, and simply select.
In this example, the Input Data Tool lets you connect to an SQL Server Database.
Using the Select Tool allows you change the data type, select/deselect fields, or simply rename the fields to whatever you want. In this case, Customer ID is the field name.
In Alteryx, combining multiple datasets is easy with the Join Tool.
The Join Tool allows you to join two tables with a common field (primary key) and Alteryx automatically returns three sets of records:
- Inner Join (J): the columns from the source table (L) joined with the columns in the table to join (R), matching records based on the common field(s)
- Left unjoined (L): the records of the original table (L) that have not found a match in the table to join (R)
- Right unjoined: (R): the records of the table to be joined (R) that have not found a match in the source table (L)
Here is a Join on Customer ID.
In addition to the Join Tool, Alteryx also has an In-Database Join Tool. This enables blending and analysis against large sets of data without moving the data out of the database, and provides significant performance improvements over traditional analysis methods.
The In-Database Join Tool lets you do inner, left outer, right outer, and full outer joins.
Learn more about Alteryx In-Database tools here.
The Union Tool allows you to combine multiple sets of records based on the field name or position of each column. You can easily change the order of the column headers in each set of records so they match up.
Here, two sets of records — the left un-joined records and the (inner) joined records — are joined together, producing a left outer join.
Limiting records based on specific criteria is performed using the Filter Tool. Filtering can use anything from simple comparisons to complicated, conditional statements. In this example only those records that do not contain the country United States are filtered.
In Alteryx, the Summarize Tool lets you collect data across multiple records, apply an aggregate function, and group the results by one or more fields.
In this example, the Summarize Tool lets you group by country (e.g., United Kingdom, Germany), and average the total amount per country.
You can limiting records based on specific criteria using the Filter Tool. Filtering can use anything from simple comparisons all the way to complicated, conditional statements. This example shows only those records that have average totals greater than or equal to 1000.
The Sort Tool in Alteryx allows you to order your data just the way you need it. Select the name(s) of the column(s) and choose between ascending or descending. In this example, the Average Total Amount is shown in Descending order.
Cross Join
Cross Join
In Alteryx
Using the Append Fields Tool, you can append the fields from a source input to every record of a target input. Each record of the target input will be duplicated for every record in the source input. In this example, all Distribution Center records are appended to each Customer record.
Ce workflow Alteryx ajoute les enregistrements Distribution Center à chaque enregistrement Client.
Where Between
Where Between
In SQL
In Alteryx
You can limit records to those that have field values within a specific range using the Alteryx Filter Tool. In this example the filter is Order Dates between December 1 – 31, 2016, inclusive.
Ce workflow Alteryx filtre les données des commandes situées entre le 1er et le 31 décembre 2016.
Where In
Where In
In SQL
In Alteryx
To limiting records to those with field values belonging to a set of possible alternatives, use the Alteryx Filter Tool. In this example, the filter is set to customers whose country is either the United States or the United Kingdom.
Ce workflow Alteryx filtre les clients dont le pays est soit États-Unis, soit Royaume-Uni.
Distinct
Distinct
In SQL
In Alteryx
The Unique Tool in Alteryx helps separate data into two streams, duplicate and unique records, based on the fields you choose. The field chosen in this example is country.
Distinct
Avec l’outil Unique, ce workflow Alteryx sépare les données en deux flux (enregistrements en double et uniques) en fonction des champs que vous choisissez (celui des pays dans cet exemple).