DISCONNECT — 终止数据库连接
DISCONNECT connection_name
DISCONNECT [ CURRENT ]
DISCONNECT ALL
DISCONNECT 关闭一个（或所有）到数据库的连接。
int
main(void)
{
EXEC SQL CONNECT TO testdb AS con1 USER testuser;
EXEC SQL CONNECT TO testdb AS con2 USER testuser;
EXEC SQL CONNECT TO testdb AS con3 USER testuser;
EXEC SQL DISCONNECT CURRENT; /* close con3 */
EXEC SQL DISCONNECT ALL; /* close con2 and con1 */
return 0;
}
DISCONNECT在SQL标准中被指定。