CONCEPT pgsql - PostgreSQL support DESCRIPTION On hosts with the PostgreSQL package installed, the driver can be configured to interface with the PostgreSQL database. If that is done, the driver defines the macro __PGSQL__ for LPC programs and activates a number of related efuns. -- Usage -- The interface to the PostgreSQL database is implemented through the concept of a controlling object: when opening a database connection, the LPC code has to provide a callback function. The object this function is bound to is the controlling object: all queries to the database will be issued by this object, and the responses will be sent to the callback function. The interface is also asynchronous: the pg_query() efun just queues the query with the database connection, and returns immediately. When the database has finished working the query, the callback function is called with the results. The callback function can be defined by name or by closure, and can be defined with extra parameters: #include void (int type, mixed ret, int id [, mixed extra...]) is the type of the call, identifies the query for which this call is executed: PGRES_TUPLES_OK: is the result from a query. It is either a mapping (field name as key, indexing values for n returned tuples), or an array of arrays (one per row). PGRES_COMMAND_OK: is a string which contains the server response (e.g. on INSERT or DELETE) PGRES_BAD_RESPONSE, PGRES_NONFATAL_ERROR, PGRES_FATAL_ERROR: ret is the error-string void (int type, mixed ret [, mixed extra...]) is the type of the call, which is not related to a specific query: PGCONN_SUCCESS: The database-connection was established, is a dummy string. PGCONN_FAILED: The database-connection failed, is the error message. The first message to the callback after a call to pg_connect() is always one of these two. PGRES_NOTICE: is a informational text. PGCONN_ABORTED: If the connection to the backend fails we try to re-establish (reset) it. If the reset fails, the connection is closed and this value is returned. Consider the connection gone and don't try to close or otherwise operate further on it. is a dummy string. -- Security -- All SQL efuns (unless execute by the master or the simul-efun object) trigger a privilege_violation ("pgsql", ""). If a more finegrained control is desired, overload the individual efuns with a nomask simul-efun. AUTHOR Florian Heinz and others. HISTORY Added as package in LDMud 3.3.445. LDMud 3.3.640 added a privilege_violation() call for each efun. SEE ALSO mysql(C), pg_connect(E), pg_conv_string(E), pg_query(E), pg_pending(E), pg_close(E), privilege_violation(M)