devxlogo

Grouping By One Field When Selecting Several

Grouping By One Field When Selecting Several

Question:
These are the fields of my table: id, email, firstname, and lastname. There can be multiple records for a single email. I only want to group by email and get a count of how many records have the same email for each group. The fields I need for the report are firstname, lastname, email, and emailcount. If two records have the same email but different firstname or lastname, I only need to see one of them in the recordset.

Answer:
You can use a query with the GROUP BY clause to retrieve a count of columns that contain the same information. For example, assume you have a table with the four columns you specified and four records, two of which have the same e-mail address. This query returns the count of records with the specified e-mail address:

 SELECT Count(*) AS emailcount, email FROM UsersGROUP BY emailemailcount email                     ---------- ----------------------- 2          [email protected]          [email protected]          [email protected]

This query gets a little fancier and groups by the additional columns in the table. Only columns in the GROUP BY clause can be returned in a GROUP BY query.

SELECT Count(*) AS emailcount, email, firstname, lastname FROM UsersGROUP BY email, firstname, lastnameemailcount email                  firstname lastname   ---------- ---------------------- --------- --------2          [email protected]        Anne      Smith1          [email protected]        Jack      Jones1          [email protected] Mary      Murray

See also  5 Tips for Working With an Onsite Interpreter
devxblackblue

About Our Editorial Process

At DevX, we’re dedicated to tech entrepreneurship. Our team closely follows industry shifts, new products, AI breakthroughs, technology trends, and funding announcements. Articles undergo thorough editing to ensure accuracy and clarity, reflecting DevX’s style and supporting entrepreneurs in the tech sphere.

See our full editorial policy.

About Our Journalist