Can we create multicolumn unique indexes on MS access databases? -

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We want to prevent duplication of records in our MS Access database by using a multicolumn unique index. Due to how data is sent (through the network), duplicate data is sometimes received. The data source does not send a unique ID, so the easiest option is to prevent duplicate records from being placed. According to

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With multicolumn unique indexes, the index guarantees that each combination of values ​​in the index key is unique. For example, if a unique index LastName , FirstName, and MiddleName columns, any two rows in the table can not have the same combination of values ​​for these columns.

This is for SQL 2005, so I'm not sure that it is possible to use MS Access.

I think a choice is probably to use the query (pseudo-code): 

  ('x', 'y', 'z') where (a & Lt; & gt; 'x') and (b & gt; & gt; 'Y') and (c & lt); & Gt; 'Z')

... but I think an index would be better. Open the table in the Design view in MS Access, select the three columns that you want to create in the unique index:

, And then click on the small key on the toolbar. You do not have a zero value in the primary key.


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