When using SQL (Structured Query Language), the order of operation is very important. Below is the order of operation to help you get it write:
- Select - This is similar to the select tool within Alteryx, in that it allows us to select the specific data we require from the database.
Syntax: SELECT ”column_name” or SELECT DISTINCT “column_name” which allows you to return only different values.
Example: SELECT * - The asterisk selects all the data from your data source.
2. From - Specify which table to select data from.
Syntax: FROM ”table_name”
Example: FROM "Superstore_Orders"
3. Where - This clause is used to extract information for records that fulfill your specific criterion.
Syntax: WHERE “column_name” operator value;
Example: WHERE “Region” = 'Central' and “Sales” > 1000
4. Group By - Similar to the summarise tool in Alteryx in that it allows us to aggregate to the dimension level.
Syntax: GROUP BY column_name
Example: GROUP BY "State"
5. Having - Similar to the WHERE clause for but for aggregated functions.
Syntax: aggregate_function(column_name) operator value
Example: HAVING AVG ("Profit") > 500
6. Order By - Used to sort the result set in ascending or descending order.
Syntax: ORDER BY column_name DESC/ASC
Example: ORDER BY AVG("Profit") DESC