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CDSC interface
The CDSC interface is a cut down version of the ADO and ADOX interfaces. By default, SQL parsing and expression parsing are handled in the UNICOM Intelligence OLE DB Provider (called the Provider).
You can optionally implement expression evaluation and aggregation services in the CDSC. If they are not implemented in the CDSC, the Provider uses the default expression evaluation and aggregation services implemented in the Evaluate object reference and SQL Aggregator components.
The services that are supported by the CDSC are published using the ISource properties collection.
Properties
Aggregates
Indicates whether the CDSC can do aggregation (that is, whether it supports aggregated expression binding). This property is applicable to the DataBindings collection on the Command object. If set to False, the Provider does not attempt to add aggregated expression bindings to the data bindings collection. (Read only.)
Default: False.
Data type: Boolean
Can Add
Indicates whether the CDSC supports adding new records to (inserting new rows in) the data for existing variables. If this property is set to False, the Provider does not attempt to call the AddNew method on Command objects. If the AddNew method is not supported, Insert SQL and rowset add new are not available. (Read only.)
Default: False.
Data type: Boolean
Can Delete
Indicates whether the CDSC supports removing records from the data for existing variables (row deletion). If this property is set to False, the Provider does not attempt to call the Delete method on Command objects. If the Delete method is not supported, Delete SQL and rowset delete are not available. (Read only.)
Default: False.
Data type: Boolean
Can Select
Indicates whether the CDSC supports reading existing data (row selection and movement). If this property is set to False, the Provider does not attempt to call the Move methods on Command objects. If the Move methods are not supported, SQL Select commands and recordsets are not available. (Read only.)
Default: True.
Data type: Boolean
Can Update
Indicates whether the CDSC supports changing the data in existing records (command row updates). If this property is set to False, the Provider does not attempt to call the Update method on Command objects (except for AddNew if Can Add is implemented). If the Update method is not supported, Update SQL and rowset update are not available. (Read only.)
Default: False.
Data type: Boolean
DDL Column
Indicates whether the CDSC supports the creation and deletion of columns in top-level tables, that is, the VDATA, HDATA, and SDATA tables. This property is applicable to the Columns collection of the Table object. If set to False, the Provider does not attempt to add columns to existing top-level tables in response to Alter Table DDL. (Read only.)
Default: False.
Data type: Boolean
DDL Hierarchical Column
Indicates whether the CDSC supports the creation and deletion of columns in child (lower-level) tables under the hierarchical HDATA table. If set to False, the Provider does not attempt to add columns to existing child tables under the HDATA table. (Read only.) Default: False.
Data type: Boolean
DDL Hierarchical Table
Indicates whether the CDSC supports the creation and deletion of child (lower-level) tables under the hierarchical HDATA table. If set to False, the Provider does not attempt to add child tables under an existing HDATA table. (Read only.) Default: False.
Data type: Boolean
DDL Table
Indicates whether the CDSC supports the creation and deletion of new top-level tables, that is, the VDATA, HDATA, and SDATA tables. If set to False, the Provider does not attempt to add top-level tables to the Tables collection of the Source object. (Read only.)
Default: False.
Data type: Boolean
Expressions
Indicates whether the CDSC can evaluate some or all variable expressions (that is, whether it supports expression binding). This property is applicable to the DataBindings collection on the Command object. If set to False, the Provider does not attempt to add expression bindings to the data bindings collection. (Read only.)
Default: False.
Data type: Boolean
HDATA
Indicates whether the CDSC supports the hierarchical HDATA table. This table contains columns for the normal variable types (mtBoolean, mtLong, mtDouble, mtText, mtDate, and mtObject, and mtCategorical) at the top level, plus columns of type mtLevel for sub-tables representing the lower levels in hierarchical data. If this property is set to False, the Provider does not attempt to create or read from the HDATA virtual table. (Read only.)
Default: False.
Data type: Boolean
Max Commands
The maximum number of concurrent commands supported by the CDSC. An attempt to exceed the maximum number of concurrent commands generates an error. A value of 0 indicates that the CDSC places no limit on the number of concurrent commands. (Read only.)
Default: 0.
Data type : Long
Max Text Size
The maximum size of a text column (an mtText variable value) in characters. A value of 0 indicates that the CDSC places no limit on the maximum number of characters in a text column. (Read only.)
Default: 255.
Data type: Long
Scroll Backward
Indicates whether the CDSC supports traversing the data backwards from the last record to the first (backward cursor movement). This property is applicable to the MoveLast and MovePrevious methods on the Command object. (Read only.) Default: False.
Data type: Boolean
SDATA
Indicates whether the CDSC supports the SDATA table. This table contains summary data about the variables, such as the number of cases in each category of a variable. If this property is set to False, the Provider does not attempt to create or read from the SDATA tables. (Read only.)
Default: False.
Data type: Boolean
Stream Binary
Indicates whether the CDSC supports streamed binary objects. This property is applicable to the GetChunk and AppendChunk methods on the Value object. (Read only.)
Default: False.
Data type: Boolean
Transactions
Indicates whether the CDSC supports transactions. This property is applicable to the transaction control methods, BeginTrans, CommitTrans, and RollbackTrans. (Read only.)
Default: False.
Data type: Boolean
Use Binding Properties
Indicates whether the CDSC supports binding object properties. Binding object properties are optional and are used to implement advanced features that are otherwise implemented as default services in the Provider and the SQL Aggregation component. (Read only.) Default: False.
Data type : Boolean
Use Command Properties
Indicates whether the CDSC supports command object properties. Command object properties are optional and are used to implement advanced features that are otherwise implemented as default services in the Provider and the SQL Aggregation component. (Read only.) Default: False.
Data type: Boolean
Use Group By
Indicates whether the CDSC can interpret SQL Group By clauses (that is, the GroupByBindings property on the Command object can be used). The GroupByBindings property is used to implement aggregation in the CDSC. By default, aggregation is performed in the Provider and the SQL Aggregation component. (Read only.) Default: False.
Data type: Boolean
Use Having
Indicates whether the CDSC can interpret SQL Having clauses (that is, whether the HavingClause property on the Command object can be used). The HavingClause property is used to implement aggregation in the CDSC. By default, aggregation is performed in the Provider and the SQL Aggregation component. (Read only.) Default: False.
Data type: Boolean
Use Order By
Indicates whether the CDSC can interpret SQL Order By clauses (that is, whether the OrderByBindings property on the Command object can be used). The OrderByBindings property is used to implement sorting in the CDSC. By default, sorting is performed in the Provider and the SQL Aggregation component. (Read only.) Default: False.
Data type: Boolean
Use Where
Indicates whether the CDSC can interpret SQL Where clauses (that is, whether the WhereClause property on the Command object can be used). The WhereClause property is used to implement Where expression evaluation in the CDSC. By default, Where clause expression evaluation is performed in the Provider and the Evaluate component. (Read only.) Default: False
Data type: Boolean
VDATA
Indicates whether the CDSC supports the VDATA table. This table contains columns for the normal variable types of mtBoolean, mtLong, mtDouble, mtText, mtCategorical, mtDate, and mtObject, and not mtLevel. VDATA is suitable for non-hierarchical data, but it can contain hierarchical data, if the data at the upper levels is repeated for each lower-level case to which it relates. If this property is set to False, the Provider does not attempt to create or read from the VDATA table. (Read only.) Default: True.
Data type: Boolean
Version
The version of the CDSC. (Read only.) Default: None.
Data type: String
See
CDSC interface: Object model
See also
Creating a CDSC
Architecture of the UNICOM Intelligence Data Model
UNICOM Intelligence Data Model reference