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PROPERTY: |
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cursorLocation |
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DESCRIPTION: |
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Indicates the location of the cursor service. |
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PROPERTY OF: |
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VALUE: |
EFFECT: |
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0 |
Client (Use the Microsoft client cursor) (Default) |
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1 |
Server (Use the cursor support supplied by the data provider) |
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2 |
None (Not use the cursor services) |
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DESCRIPTION: |
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The cursorLocation property allows you to choose between various cursor libraries accessible to the provider. |
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Usually, you can choose between using a client-side cursor library or one that is located on the server. |
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A cursor is used to : control record navigation, control the visibility of changes in the database, control the updatability of data. |
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A client-side cursor offers more flexibility. All data is retrieved to the local machine and then operated on there, |
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allowing operations not normally supported by servers like sorting and resorting the data and additional filtering. |
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SQL statements are executed at the server, so for statements that restrict the result set with a WHERE clause, only the reduced result set is retrieved to a local cursor. |
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A server-side cursor offers less flexibility, but may be more advantageous (or necessary) for large result sets. |
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Using a server-side cursor becomes necessary when the sheer size of a result set exceeds the available disk space that would be needed to create the client-side cursor. |
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Also, many servers only support unidirectional cursors. This would preclude moving the record pointer in the dataset backward (even one record) through the result set. |
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The cursorLocation property setting affects connections established only after the property has been set. |
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Changing this property has no effect on existing connections. |
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A data-source objects inherits the cursorLocation property setting from the associated ADODatabase object. |
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For the directly returning of data from the ADODatabase (executeSQL() and getSchema() methods) the location of cursor determine what |
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cursor type will be used by default (usually the Static or Forward-only type of cursor). |
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This property is read/write on a ADODatabase object. |
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This property is read-only on an open data-source objects. |
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