Custom connection properties used by the UNICOM Intelligence Data File CDSC
This topic describes the custom connection properties that are unique to the UNICOM Intelligence Data File CDSC.
You can specify custom connection properties by adding the MR Init Custom or MR Custom connection property to the connection string. The format is:
MR [Init] Custom = "<property name> = <value>(; <property name> = <value>)*"
For example:
MR Init Custom = "MaxMultiCol = 0; TransactionMode = 0"
Use the MR Init Custom property when you connect using the UNICOM Intelligence OLE DB Provider, for example, in DM Query or in a data management (.dms) script. If you are passing connection properties to a UNICOM Intelligence Data File CDSC object that you have created programmatically, use the MR Custom property.
For a list of all the standard connection properties that are available to the UNICOM Intelligence Data File CDSC, see
Connection properties.
Properties
ConnectionPerCommand
True opens a new connection to the underlying SQLite database; it opens one connection for each Command object that is created by the caller. This improves performance for applications that run multiple data accesses in parallel.
The default value is False.
Encoding
A string value that can be used to specify the encoding when creating a UNICOM Intelligence Data File. The valid values are UTF-8 and UTF-16. The values are not case-sensitive. The default is UTF-8. If your metadata and case data consist only of single-byte characters, the resulting UNICOM Intelligence Data File should be smaller when the encoding is UTF-8.
MaxMultiCol
A long value that specifies the maximum number of integer columns to create in a level table for each Metadata Model (MDM) categorical variable. If the value of the MDM variable's
EffectiveMaxValue property exceeds the value of MaxMultiCol, a single text column is created instead to store the categorical response. The default value is 1, which means that single-response categoricals will be stored in an integer column, and multiple-response categoricals will be stored in a text column. To store all categorical variables in text columns, set the value of MaxMultiCol to 0. For more information, see
Columns in the L1, L2, L3, ... Ln tables.
In general, fewer columns results in better performance, but might also result in a larger file size. Performance can become unacceptable if the value of MaxMultiCol is set to greater than 10.
PageSize
A long value that defines the page size to use when creating a UNICOM Intelligence Data File. The allowed values are 512, 1024, 2048, 4096, 8192, 16384, and 32768. The default is 32768.
In general, a large page size results in better performance when reading a UNICOM Intelligence Data File, but page size has no significant effect when writing data to the file. However, for a small data set, a large page size can result in a much larger file size.
TransactionMode
A long value that determines whether the UNICOM Intelligence Data File CDSC uses transactions. A value of 1 specifies that the UNICOM Intelligence Data File CDSC wraps up all data manipulation statements executed during a single connection into a single transaction, which is always committed. A value of 0 specifies that the UNICOM Intelligence Data File CDSC will not use transactions. The default is 1, which results in significantly better performance when using the UNICOM Intelligence Data File CDSC for data management tasks.
UpdateIndexes
A Boolean value that determines whether the UNICOM Intelligence Data File CDSC needs to update indexes at the initialize stage. A value of True specifies that the UNICOM Intelligence Data File CDSC will update indexes in the initialize stage. The default value is False, which results in the indexes not being updated even if the Index definition was changed in the .mdd document. This value can help eliminate unneeded processing overhead.
See also