Updatable Query Support

You can call queries as views by using a FROM clause in a SELECT statement. The restrictions on updating views depend on the query on which the view is based. If a query is updatable by using SQLSetPos, the view that is based on the query is also updatable. Updatability is not affected by how the SQL query is executed. For example, it does not matter whether the SQL query is executed by including an SQL string in a call to the SQLExecDirect function, or by executing a stored query.

Queries based on a single table and queries based on tables with a one-to-one relationship are updatable. Queries based on tables with a one-to-many relationship are usually updatable. The following queries are not updatable:

• Aggregation queries (for example, Sum or Count)
  
  
• UNION queries
  
  
• Queries whose UniqueValues property is set to Yes
  
  
• Queries that include an attached ODBC table with no unique index or a Paradox table without a primary key
  
  
• Queries (or underlying tables) for which update or delete permission isn’t granted
  
  
• Queries that include more than one table or query, where the tables or queries are not joined by a join line in Microsoft Access query Design view
  
  
• Queries that include a calculated field
  
  
• Queries that include a read-only field
  
  
• Queries that include a field in a record that has been deleted or locked by another user

See Also For more information about queries, see Chapter 4, “Queries.”