Understand ways to sum data. Prepare some sample data. Sum data by using a Total row. Calculate grand totals by using a query. Calculate group totals by using a totals query. Sum data across multiple groups by using a crosstab query. Aggregate function reference. You can sum a column of numbers in a query by using a type of function called an aggregate function. Aggregate functions perform a calculation on a column of data and return a single value.
Access provides a variety of aggregate functions, including Sum , Count , Avg for computing averages , Min and Max. You sum data by adding the Sum function to your query, you count data by using the Count function, and so on. In addition, Access provides several ways to add Sum and other aggregate functions to a query.
You can:. Open your query in Datasheet view and add a Total row. The Total Row, a feature in Access, allows you to use an aggregate function in one or more columns of a query result set without having to change the design of your query. Create a totals query. A totals query calculates subtotals across groups of records; a Total row calculates grand totals for one or more columns fields of data. For example, if you want to subtotal all sales by city or by quarter, you use a totals query to group your records by the desired category and you then sum the sales figures.
Create a crosstab query. A crosstab query is a special type of query that displays its results in a grid that resembles an Excel worksheet. Crosstab queries summarize your values and then group them by two sets of facts — one set down the side row headings , and the other across the top column headings. For example, you can use a crosstab query to display sales totals for each city for the past three years, as the following table shows:.
Note: The how-to sections in this document emphasize using the Sum function, but remember that you can use other aggregate functions in your Total rows and queries. For more information about using the other aggregate functions, see the section Aggregate function reference later in this article.
For more information about ways to use the other aggregate functions, see the article Display column totals in a datasheet. The steps in the following sections explain how to add a Total row, use a totals query to sum data across groups, and how to use a crosstab query that subtotals data across groups and time intervals. As you proceed, remember that many of the aggregate functions work only on data in fields set to a specific data type. For more information about the data types that each function requires, see the section Aggregate function reference , later in this article.
For general information about data types, see the article Modify or change the data type set for a field. The how-to sections in this article provide tables of sample data. The how-to steps use the sample tables in order to help you understand how the aggregate functions work. If you prefer, you can optionally add the sample tables into a new or existing database. Access provides several ways to add these sample tables to a database.
You can enter the data manually, you can copy each table into a spreadsheet program such as Excel and then import the worksheets into Access, or you can paste the data into a text editor such as Notepad and import the data from the resulting text files.
The steps in this section explain how to enter data manually in a blank datasheet, and how to copy the sample tables to a spreadsheet program, and then import those tables into Access. For more information about creating and importing text data, see the article Import or link to data in a text file. The how-to steps in this article use the following tables.
Use these tables to create your sample data:. Note: Remember that in a typical database an order details table will contain only a Product ID field, not a Product Name field. The sample table uses a Product Name field to make the data easier to read. On the Create tab, in the Tables group, click Table. Note: You do not need to follow this step if you open a new, blank database, but you will need to follow it whenever you need to add a table to the database.
Double-click the first cell in the header row and enter the name of the field in the sample table. By default, Access denotes blank fields in the header row with the text Add New Field , like so:.
Use the arrow keys to move to the next blank header cell , and type the second field name you can also press TAB or double-click the new cell. Repeat this step until you enter all field names. As you enter the data, Access infers a data type for each field. Setting the data type helps ensure accurate data entry and also helps prevent mistakes, such as using a telephone number in a calculation. For these sample tables, you should let Access infer the data type.
In the Table Name box, enter the name of the sample table, and then click OK. You use the name of each sample table because the queries in the how-to sections use those names. Repeat these steps until you create each of the sample tables listed at the beginning of this section.
If you do not want to enter the data manually, follow the next steps to copy the data to a spreadsheet file, and then import the data from the spreadsheet file into Access. Start your spreadsheet program and create a new, blank file.
If you use Excel, it creates a new, blank workbook by default. Copy the first sample table provided above and paste it into the first worksheet, starting at the first cell. Contents Exit focus mode. Please rate your experience Yes No. Any additional feedback?
In this article. One hundred fields is an awful lot of fields. You probably need to break the 'spreadsheet' format into related tables. Post your field list with datatype. Explain the purpose of the data collection. A delete query needs to have criteria so as to only remove the proper records. How satisfied are you with this reply? Thanks for your feedback, it helps us improve the site. Scottgem MVP. You are making a mistake by trying to duplicate a spreadsheet cell structure in Access.
Access is not a spreadsheet, its a relational database. Use the power of a relational database to your advantage. I actually knew they were records and fields, I apologize for calling them cells rows and columns.
I have discussed using multiple tables with my boss and he wants them left in the 2 tables based on the company we're collecting the information from. Therein lies my problem. You cannot undo the results of an update query, and making a backup helps make sure that you can reverse your changes if you change your mind.
Click the File Tab, and then click Save As. In the Save Backup As dialog box, specify a name and location for the backup copy, and then click Save. To revert to a backup, close and rename the original file so that the backup copy can use the name of the original version.
Assign the name of the original version to the backup copy, and then open the renamed backup copy in Access. Step 1: Create a select query to identify the records to update. Step 2: Update the records. On the Create tab, in the Queries group, click Query Design.
Select the table or tables that contain the records that you want to update, click Add , and then click Close. The table or tables appear as one or more windows in the query designer, and the windows list all the fields in each table. This figure shows the query designer with a typical table.
Double-click the fields that you want to update in the table windows. The selected fields appear in the Field row in the query design grid. This figure shows the query design grid with all the fields added. To limit the query results based on field values, in the query design grid, in the Criteria row, enter the criteria that you want to use to limit the results.
The following table shows some example criteria and explains the effect that they have on the results of a query. Note: Many of the examples in this table use wildcard characters to make the query more flexible or powerful.
If your database uses the ANSI wildcard characters, use single quotation marks ' instead of pound signs. Finds all records where the exact contents of the field are not exactly equal to "Germany. Finds all records except those starting with T.
Finds all records that do not end with t. In a text field, finds all records that start with the letters A through D. Finds all records that include the letter sequence "ar". Finds all records that begin with "Maison" and contain a 5-letter second string in which the first 4 letters are "Dewe" and the last letter is unknown. Finds all records for February 2, Uses the Date function to return all records containing today's date. Uses the Date and DateAdd functions to return all records between today's date and three months from today's date.
Returns all records that contain a zero-length string. You use zero-length strings when you need to add a value to a required field, but you don't yet know what that value is. For example, a field might require a fax number, but some of your customers might not have fax machines.
In that case, you enter a pair of double quotation marks with no space between them "" instead of a number. On the Design tab, in the Results group, click Run. To add any fields that you want to include in the query design, drag the additional fields to the query design grid. On the Design tab, in the Query Type group, click Update. This procedure shows you how to change a select query to an update query.
When you do this, Access adds the Update to row in the query design grid. The following illustration shows an update query that returns all the assets purchased after January 5, and changes the location to "Warehouse 3" for all the records that meet that criterion. Locate the field that contains the data that you want to change, and then type your expression your change criteria in the Update to row for that field. Where the ProductID values in the current table match the ProductID values in table named Order Details, this expression updates sales totals by multiplying the values in a field named Quantity by the values in a field named UnitPrice.
The expression uses the DSum function because it can operate against more than one table and table field. Truncates removes the leftmost characters in a text or numeric string and leaves the 5 rightmost characters.
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