When creating a query with multiple tables, fields can be added to the design grid
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Create a Query to Combine Data from Two Tables with Similar StructuresProblemYou have two tables of addresses, one for clients and one for leads. Generally you send different mailings to these two groups, but sometimes you need to send the same letter to both. You can always create a third table and append to it the data from each of the two tables, but there must be an easier way that doesn’t involve the use of temporary tables. Is there a way to combine the data from these two tables into a single recordset, including only the U.S. addresses and sorted by zip code? SolutionAccess provides a special type of query that you can use to vertically splice together the data from two or more tables. The tables don’t even need to have the same fields or fields of exactly the same data types. This is the union query, which can be constructed only by using the SQL View pane in the query designer. The following steps show you how to construct a union query to combine data from two tables into a single recordset, limited to addresses in the U.S. and sorted by zip code:
Discussion The SQL If a matching field is absent from one of the tables—as is the case for tblLeads, which lacks an Address3 field—you can
include a constant. In the qryCombinedLists example, we used a zero-length string constant (“”), but we could have used another constant, such as You can also add a column called Type that contains either “Client” or “Lead”, depending on which table it comes from, as shown in qryCombinedListswType in the sample database. Here’s the SQL for that query: SELECT Company, Address1, Address2, Address3, City, StateProvince, ZipPostalCode, Country, "Client" AS Type FROM tblClients WHERE Country = "U.S.A." UNION SELECT LeadName, Address1, Address2, "", City, State, Zip, Country, "Lead" AS Type FROM tblLeads WHERE Country = "U.S.A." ORDER BY ZipPostalCode; While typing in the text of the union query, you may find it helpful to keep the source tables open in
design view so you can be sure you are entering the field names correctly. Or you can just “cheat” and use the query designer to create Some dialects of SQL require the SQL statement to end with a semicolon. Access does not, but it doesn’t hurt to use the standard syntax, especially if you program in other databases too. A union query is a snapshot of the data in the underlying tables, so it can’t be updated. To sort a union query, add one TipA union query automatically screens out duplicate records (if any); if you want to include duplicates in the query’s result set, use
Get Access Cookbook now with the O’Reilly learning platform. O’Reilly members experience live online training, plus books, videos, and digital content from nearly 200 publishers. Can a query include fields from multiple tables?Double-click the two tables that contain the data you want to include in your query and also the junction table that links them, and then click Close. All three tables appear in the query design workspace, joined on the appropriate fields. Double-click each of the fields that you want to use in your query results.
How many fields can you add to the query design grid in Access?There is a limit - but it's 255 fields. The Grid is not the query, it's just a (somewhat quirky and limited) tool to build queries. Scott described how to add more columns in the grid; you can also switch the query to SQL view and edit the REAL query.
How can I create a multi table query in query design view?To create a multi-table query:. Select the Query Design command from the Create tab on the Ribbon.. In the dialog box that appears, select each table you want to include in your query and click Add. ... . After you have added all of the tables you want, click Close.. How many fields can you add to the query design grid quizlet?The maximum number of fields to add to the grid is ten.
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