Re: Patch: Implement failover on libpq connect level.

+ /*

+ * consult connection options and check if RO connection is OK

+ * RO connection is OK if readonly connection is explicitely

+ * requested or if replication option is set, or just one

+ * host is specified in the connect string.

+ */

+ if ((conn->pghost==NULL || strchr(conn->pghost,',')==NULL) ||

+ ((conn->read_only && conn->read_only[0] > '0'))

+ ||(conn->replication && conn->replication[0])

+ )

+ {

Now if only one host is in connection string and it ask for read_write connection(connect to master) I mean read_only is set 0 explicitly. With above logic we will allow it to connect to standby?. I still think psql connection to standby should be handled by changing the default value of readonly to 1 (which means connect to any). Thinking further probably replacing readonly parameter with targetServerType=any|master (with default being any) should clear some confusions and bring consistency since same is used in JDBC multi host connection string.