IBM DB2 Manual page 224

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208
Application Programming Guide and Reference for Java
DB2BaseDataSource.NOT_SET (0)
The IBM Data Server Driver for JDBC and SQLJ does not use seamless
failover. This is the default.
fetchSize
Specifies the number of result set rows that is the default fetch size for
ResultSet objects that are generated from Statement objects. The data type of
this property is int.
The fetchSize default can be overridden by the Statement.setFetchSize
method. The fetchSize property affects only scrollable cursors and does not
affect Statement objects that already exist when fetchSize is set.
Possible values of fetchSize are:
0 or positive-integer
The default fetchSize value for newly created Statement objects. If the
fetchSize property value is invalid, the IBM Data Server Driver for
JDBC and SQLJ sets the default fetchSize value to 0.
DB2BaseDataSource.FETCHSIZE_NOT_SET (-1)
Indicates that the default fetchSize value for Statement objects is 0. This
is the property default.
The fetchSize property differs from the queryDataSize property in the
following ways:
v The fetchSize property applies to connections to all data sources that are
supported by the IBM Data Server Driver for JDBC and SQLJ. The
queryDataSize property applies only to IBM Data Server Driver for JDBC
and SQLJ type 4 connectivity to DB2 for z/OS and DB2 Database for Linux,
UNIX, and Windows, and to IBM Data Server Driver for JDBC and SQLJ
type 2 connectivity to DB2 Database for Linux, UNIX, and Windows.
v For scrollable cursors, fetchSize controls the amount of data that is returned
from the data source. A single response from the data source always
contains up to fetchSize rows. The queryDataSize property has no impact on
the total amount of data that is returned.
v For forward-only cursors, the amount of data that is returned from the data
source in a single response is determined only by queryDataSize. The
fetchSize property has no impact on forward-only cursors.
fullyMaterializeLobData
Indicates whether the driver retrieves LOB locators for FETCH operations. The
data type of this property is boolean.
The effect of fullyMaterializeLobData depends on whether the data source
supports progressive streaming, which is also known as dynamic data format:
v If the data source does not support progressive streaming:
If the value of fullyMaterializeLobData is true, LOB data is fully
materialized within the JDBC driver when a row is fetched. If the value is
false, LOB data is streamed. The driver uses locators internally to retrieve
LOB data in chunks on an as-needed basis It is highly recommended that
you set this value to false when you retrieve LOBs that contain large
amounts of data. The default is true.
v If the data source supports progressive streaming:
The JDBC driver ignores the value of fullyMaterializeLobData if the
progressiveStreaming property is set to DB2BaseDataSource.YES or
DB2BaseDataSource.NOT_SET.
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