How to use an Access query

Assuming that there is a "Fleet transport" table, there is a "driver, cargo category, gross weight, tare" field. We will use it as the raw data, through the query to the data calculation and statistics.

Driver	Type of goods	Gross weight	Tare
Li Dafang	Other	75.00	25.00
Zhao Beautiful	Other	75.00	25.00
Zhang Cute	Other	150.00	50.00
Zhao Beautiful	Fine Powder	19.70	5.40
Zhang Cute	Fine Powder	20.70	5.40
Zhang Cute	Fine Powder	20.60	5.40
Zhang Cute	Ore	19.60	5.40
Zhang Cute	Fine Powder	20.60	5.40
Zhang Cute	Fine Powder	21.10	5.40
Zhang Cute	Ore	21.20	5.40
Li Dafang	Fine Powder	17.40	5.40
Zhao Beautiful	Waste Stone	120.00	40.00
Zhao Beautiful	Other	15.00	5.00
Li Dafang	Waste Stone	105.00	35.00
Zhang Cute	Waste Stone	105.00	35.00
Zhao Beautiful	Waste Stone	105.00	35.00

1. Create a calculated field with a select query

Build a Select query, add the "Fleet Transport" table, and drag all of its fields to the design grid. As shown in figure, as long as the "net weight: Gross weight-tare" is filled in the blank column, the system automatically adds "[]" to the "gross weight" and "tare" to indicate that they are fields. Save this query as "Fleet transport inquiries".

The following table is the newly produced Fleet Transport query, the net weight is calculated automatically:

Driver	Type of goods	Gross weight	Tare	Net
Li Dafang	Other	75.00	25.00	50.00
Li Dafang	Other	135.00	45.00	90.00
Zhao Beautiful	Other	75.00	25.00	50.00
Zhang Cute	Other	150.00	50.00	100.00
Zhao Beautiful	Fine Powder	19.70	5.40	14.30
Zhang Cute	Fine Powder	20.70	5.40	15.30
Zhang Cute	Fine Powder	20.60	5.40	15.20
Zhang Cute	Ore	19.60	5.40	14.20
Zhang Cute	Fine Powder	20.60	5.40	15.20
Zhang Cute	Fine Powder	21.10	5.40	15.70
Zhang Cute	Ore	21.20	5.40	15.80
Li Dafang	Fine Powder	17.40	5.40	12.00
Zhao Beautiful	Waste Stone	120.00	40.00	80.00
Zhao Beautiful	Other	15.00	5.00	10.00
Li Dafang	Waste Stone	105.00	35.00	70.00
Zhang Cute	Waste Stone	105.00	35.00	70.00
Zhao Beautiful	Waste Stone	105.00	35.00	70.00