JDBC Type 4 Driver 3.0 Programmer's Reference (SQL/MX 3.x)

maxStatements Property
The maxStatements property sets the total number of PreparedStatement objects that the
connection pool should cache. This total includes both free objects and objects in use. The Type 4 driver
Side Cache uses Most Frequently Used (MFU) algorithm. When the number of
PreparedStatements in the cache exceeds the specified maxStatements property, the least used
PreparedStatement is closed and removed from the statement cache to make way for a new
statement.
Set this property on a DataSource object, ConnectionPoolDataSource object, or
DriverManager object. For information about how to set properties, see How to Specify JDBC Type
4 Properties.
Data type: int
Units: number of objects
Default: 0 (Disables statement pooling.)
Range: 0 through 2147483647
The value 0 disables statement pooling. Any negative value is treated like 0 (zero).
Performance tip: HP recommends that you enable statement pooling for your JDBC applications
because this pooling can dramatically help the performance of many applications.
For example, to specify statement pooling, type: maxStatements=10
The Prepared Statement Caching algorithm is updatedfor each SQL prepared statement, a number is
assigned starting with one. The assigned number increments by one whenever the statement is prepared
again. This technique helps in selecting the prepared statements to be removed from the NonStop JDBC
Type 4 Driver 3.0 cache. The prepared statements, which are not in use but are in cache, are selected and
sorted based on the number assigned previously. The prepared statement, whose number is the least, is
removed from the cache.
minPoolSize Property
The minPoolSize property limits the number of physical connections that can be in the free
connection pool.
Set this property on a DataSource object, ConnectionPoolDataSource object, or
DriverManager object. For information about how to set properties, see How to Specify JDBC Type
4 Properties.
Data type: int