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Property
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Characteristic
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Determines which type of metadata information is included in result sets when an application calls DatabaseMetaData methods.
If set to 2, result sets do not contain synonyms.
If set to 4, a hint is provided to the driver to emulate getColumns() calls using the ResultSetMetaData object instead of querying database catalogs for column information. Result sets contain synonyms. Using emulation can improve performance because the SQL statement that is formulated by the emulation is less complex than the SQL statement that is formulated using getColumns(). The argument to getColumns() must evaluate to a single table. If it does not, because of a wildcard or null value, for example, the driver reverts to the default behavior for getColumns() calls.
The default is 2.
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Controls how data conversions are handled for null values.
If set to 0, the driver does not perform the data type check if the value of the column is null. This allows null values to be returned even though a conversion between the requested type and the column type is undefined.
If set to 1, the driver checks the data type being requested against the data type of the table column that stores the data. If a conversion between the requested type and column type is not defined, the driver generates an "unsupported data conversion" exception regardless of whether the column value is NULL.
The default is 1.
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Specifies the maximum number of rows that the driver processes before returning data to the application for a single fetch request when executing a Select. This value provides a suggestion to the driver as to the number of rows that should be returned to the application. The driver may fetch fewer rows to conserve memory when processing exceptionally wide rows.
If set to 0, the driver processes all the rows of the result before returning control to the application. When large data sets are being processed, setting FetchSize to 0 can diminish performance and increase the likelihood of out-of-memory errors.
If set to x, the driver limits the number of rows that may be processed for each fetch request before returning control to the application.
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Specifies one or multiple SQL commands to be executed by the driver after it has established the connection to the database and has performed all initialization for the connection. If the execution of a SQL command fails, the connection attempt also fails and the driver throws an exception indicating which SQL command or commands failed.
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Determines the amount of memory used by the driver to cache insensitive result set data.
If set to -1, the driver caches insensitive result set data in memory. If the size of the result set exceeds available memory, an OutOfMemoryException is generated. With no need to write result set data to disk, the driver processes the data efficiently.
If set to 0, the driver caches insensitive result set data in memory, up to a maximum of 2 MB. If the size of the result set data exceeds available memory, then the driver pages the result set data to disk, which can have a negative performance effect. Because result set data may be written to disk, the driver may have to reformat the data to write it correctly to disk.
If set to x, the driver caches insensitive result set data in memory and uses this value to set the size (in KB) of the memory buffer for caching insensitive result set data. If the size of the result set data exceeds available memory, then the driver pages the result set data to disk, which can have a negative performance effect. Because the result set data may be written to disk, the driver may have to reformat the data to write it correctly to disk. Specifying a buffer size that is a power of 2 results in efficient memory use.
The default is 2048.
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Determines which algorithm the driver uses when converting a double or float value to a string value. By default, the driver uses its own internal conversion algorithm, which improves performance.
If set to true, the driver uses the JVM algorithm when converting a double or float value to a string value. If your application cannot accept rounding differences and you are willing to sacrifice performance, set this value to true to use the JVM conversion algorithm.
If set to false, the driver uses its own internal algorithm when converting a double or float value to a string value. This value improves performance, but slight rounding differences within the allowable error of the double and float data types can occur when compared to the same conversion using the JVM algorithm.
The default is false.
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Specifies the filename of the configuration file used to initialize driver logging.
The default is ddlogging.properties.
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Specifies whether the connection supports read-only access to the data source.
If set to true, the connection has read-only access. The following commands are the only commands that you can use when a connection if read-only:
 Call* (if the procedure does not update data)
Explain Plan
Select (except Select Into)
Set Database Collation
Set IgnoreCase
Set Maxrows
Set Schema
The driver generates an exception if any other command is executed.
If set to false, the connection is opened for read/write access, and you can use all commands supported by the product.
The default is false.
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Enables DataDirect Spy to log detailed information about calls issued by the driver on behalf of the application. DataDirect Spy is disabled by default.
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Specifies how the driver handles manual transactions.
If set to ignore, the data source does not support transactions and the driver always operates in auto-commit mode.
If set to noTransactions, the data source and the driver do not support transactions.
The default is noTransactions.
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