Development Specifications

If the connection pool mechanism is used during application development, comply with the following specifications:

• If GUC parameters are set in the connection, run SET SESSION AUTHORIZATION DEFAULT;RESET ALL; to clear the connection status before you return the connection to the connection pool.
• If a temporary table is used, delete the temporary table before you return the connection to the connection pool.

If you do not do so, the connection state in the connection pool will remain, which affects subsequent operations using the connection pool.

Table 1 describes the compatibility of application development drivers.

Table 1 Compatibility Description

Driver	Compatibility Description
JDBC and Go	The new drivers are forward compatible with the database. To use the new features added to the driver and database, you must upgrade the database.
ODBC, libpq, Psycopg, and ecpg	The driver version must match the database version.

• In principle, you need to set the compatibility parameter after the database creation, instead of switching the parameters when using the database.
• To use the features in the following scenario, you need to upgrade the JDBC driver to 503.1 or later, enable the s2 compatibility parameter, and set the validity check of sessiontimezone:

If the driver is used in a multi-thread environment:

The JDBC driver is non-thread-safe and does not guarantee that the connection methods are synchronized. The caller synchronizes the calls to the driver.