Обсуждение: Functionality
Hi I have been learning postgresql for the last couple days and I have been trying to determine what it can and cannot do in relation to Oracle (where I have several years experience). Questions 1. Can postgresql load/pin objects (i.e. tables, procedures, etc.) into memory at startup? 2. Does postgresql use a SQL cache like Oracle? If so, can the cache be viewed or summarized using SQL? 3. Is it possible to return anything other than a single value from a server-side procedure. If so, how? 4. Can SQL be parameterized like in Oracle (i.e. "SELECT name FROM table WHERE somefield = :var1")? 5. Does postgresql support SQL hints (belong using the JOIN keyword)? 6. Does postgresql use table spaces like in Oracle (i.e. database objects are placed if different tables spaces according to usage)? Thanks
> Hi > > I have been learning postgresql for the last couple days and I have been > trying to determine what it can and cannot do in relation to Oracle (where I > have several years experience). > > Questions > > 1. Can postgresql load/pin objects (i.e. tables, procedures, etc.) into > memory at startup? No. > 2. Does postgresql use a SQL cache like Oracle? If so, can the cache be > viewed or summarized using SQL? No, I don't think so. > 3. Is it possible to return anything other than a single value from a > server-side procedure. If so, how? No. > 4. Can SQL be parameterized like in Oracle (i.e. "SELECT name FROM table > WHERE somefield = :var1")? No. > 5. Does postgresql support SQL hints (belong using the JOIN keyword)? No. > 6. Does postgresql use table spaces like in Oracle (i.e. database objects > are placed if different tables spaces according to usage)? No. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 853-3000 + If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill, Pennsylvania 19026
> > 5. Does postgresql support SQL hints (belong using the JOIN keyword)? > > No. > I believe there is an explicit join syntax. Too lazy to look it up. It's more than just hints, though, it's a totally different syntax. Jon
> > > 5. Does postgresql support SQL hints (belong using the JOIN keyword)? > > > > No. > > > > I believe there is an explicit join syntax. Too lazy to look it up. It's > more than just hints, though, it's a totally different syntax. The JOIN is really not for optimizer hints, which I believe was his question. If he wants full ANSI JOIN syntax, we have that. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 853-3000 + If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill, Pennsylvania 19026