pg_transaction_status() returns the current in-transaction status of the server. The status can be PGSQL_TRANSACTION_IDLE (currently idle), PGSQL_TRANSACTION_ACTIVE (a command is in progress), PGSQL_TRANSACTION_INTRANS (idle, in a valid transaction block), or PGSQL_TRANSACTION_INERROR (idle, in a failed transaction block). PGSQL_TRANSACTION_UNKNOWN is reported if the connection is bad. PGSQL_TRANSACTION_ACTIVE is reported only when a query has been sent to the server and not yet completed.
pg_transaction_status() will give incorrect results when using a PostgreSQL 7.3 server that has the parameter autocommit set to off. The server-side autocommit feature has been deprecated and does not exist in later server versions.
Exemple 1. pg_transaction_status() example