Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Wko2J-0003Ls-Mq for pgsql-performance@arkaria.postgresql.org; Thu, 15 May 2014 05:16:55 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1Wko2J-0001yH-54 for pgsql-performance@arkaria.postgresql.org; Thu, 15 May 2014 05:16:55 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Wko2H-0001y0-1b for pgsql-performance@postgresql.org; Thu, 15 May 2014 05:16:53 +0000 Received: from bay004-omc4s4.hotmail.com ([65.54.190.206]) by magus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Wko2D-0006on-KE for pgsql-performance@postgresql.org; Thu, 15 May 2014 05:16:52 +0000 Received: from BAY174-W47 ([65.54.190.199]) by BAY004-OMC4S4.hotmail.com with Microsoft SMTPSVC(7.5.7601.22678); Wed, 14 May 2014 22:16:47 -0700 X-TMN: [i3a5LRyh0CsrGukmh+mMFESZK9lCq8Vg] X-Originating-Email: [chang-chao@hotmail.com] Message-ID: From: =?utf-8?B?5bi46LaF?= To: "pgsql-performance@postgresql.org" Subject: how do functions affect query plan? Date: Thu, 15 May 2014 14:16:47 +0900 Importance: Normal Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-OriginalArrivalTime: 15 May 2014 05:16:47.0826 (UTC) FILETIME=[DED95320:01CF6FFC] X-Pg-Spam-Score: -2.6 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org SGksYWxsCkkgaGF2ZSBhIHRhYmxlIHRvIHNhdmUgcmVjZWl2ZWQgbWVhc3Vy ZSBkYXRhLgoKCkNSRUFURSBUQUJMRSBtZWFzdXJlX2RhdGEKKArCoCBpZCBz ZXJpYWwgTk9UIE5VTEwsCsKgIHRlbGVncmFtX2lkIGludGVnZXIgTk9UIE5V TEwsCsKgIG1lYXN1cmVfdGltZSB0aW1lc3RhbXAgd2l0aG91dCB0aW1lIHpv bmUgTk9UIE5VTEwsCsKgIGl0ZW1faWQgaW50ZWdlciBOT1QgTlVMTCwKwqAg dmFsIGRvdWJsZSBwcmVjaXNpb24sCsKgIENPTlNUUkFJTlQgbWVhc3VyZV9k YXRhX3BrZXkgUFJJTUFSWSBLRVkgKGlkKQopOwoKQ1JFQVRFIElOREVYIGlu ZGV4X21lYXN1cmVfZGF0YV90ZWxlZ3JhbV9pZCBPTiBtZWFzdXJlX2RhdGEg VVNJTkcgYnRyZWUgKHRlbGVncmFtX2lkKTsKCgppbiBteSBzY2VuYXJpbyxh IHRlbGVncmFtIGNvbnRhaW5zIG1lYXN1cmUgZGF0YSBmb3IgbXVsdGlwbGUg ZGF0YSBpdGVtcyBhbmQgdGltZXN0YW1wcywKQlRXLGFub3RoZXIgdGFibGUg aXMgZm9yIHRlbGVncmFtLgoKVGhlIFNRTCBJIHVzZWQgaW4gbXkgYXBwbGlj YXRpb24gaXMgCsKgIHNlbGVjdCAqIGZyb20gbWVhc3VyZV9kYXRhIHdoZXJl IHRlbGVncmFtX2lkIGluKDEsMiwuLi4sbikKYW5kIHRoaXMgcXVlcnkgdXNl ZCB0aGUgaW5kZXhfbWVhc3VyZV9kYXRhX3RlbGVncmFtX2lkIGluZGV4LGFz IGV4cGVjdGVkLgoKSW4gb3JkZXIgdG8gc2VlIHRoZSBwZXJmb3JtYW5jZSBv ZiBteSBxdWVyeSAsCkkgdXNlZCB0aGUgZm9sbG93aW5nIHF1ZXJ5IHRvIHNl YXJjaCB0aGUgbWVhc3VyZSBkYXRhIGZvciByYW5kb21seSAzMCB0ZWxlZ3Jh bXMuCgoKZXhwbGFpbiBhbmFseXplClNFTEVDVCBtZC4qCsKgIEZST00gbWVh c3VyZV9kYXRhIG1kCsKgIHdoZXJlIHRlbGVncmFtX2lkIGluIArCoMKgwqAg KArCoMKgwqDCoMKgwqDCoMKgIFNFTEVDVCBkaXN0aW5jdArCoMKgwqDCoMKg wqDCoMKgIHRydW5jKCgxMzIzNjMtNjY0ODQpICogcmFuZG9tKCkgKyA2NjQ4 NCkKwqDCoMKgwqDCoMKgwqDCoCBGUk9NIGdlbmVyYXRlX3NlcmllcygxLDMw KSBhcyBzKHRlbGVncmFtX2lkKQrCoMKgwqAgKQrCoCA7Cgp0aGUgMTMyMzYz IGFuZCA2NjQ4NCBhcmUgdGhlIG1heCBhbmQgbWluIG9mIHRoZSB0ZWxlZ3Jh bSBpZCxzZXBhcmF0ZWx5LgoKV2hhdCBzdXJwcmlzZWQgbWUgaXMgdGhhdCBp bmRleCBpcyBub3QgdXNlZCxpbnN0ZWFkLGEgc2VxIHNjYW4gaXMgcGVyZm9y bWVkIG9uIG1lYXN1cmVfZGF0YS4KQWx0aG91Z2gsaW50dWl0aXZlbHksaW4g dGhpcyBjYXNlLGl0IGlzIG11Y2ggd2lzZXIgdG8gdXNlIHRoZSBpbmRleC4K V291bGQgeW91IHBsZWFzZSBnaXZlIHNvbWUgY2x1ZSB0byB3aHkgdGhpcyBo YXBwZW5lZD8KCiJIYXNoIFNlbWkgSm9pbsKgIChjb3N0PTY1LjAwLi41Mzkx NjkuMzIgcm93cz0xMDI3NzI4MCB3aWR0aD0yOCkgKGFjdHVhbCB0aW1lPTc2 LjQ1NC4uMTcxNzcuMDU0IHJvd3M9OTM2MCBsb29wcz0xKSIKIsKgIEhhc2gg Q29uZDogKChtZC50ZWxlZ3JhbV9pZCk6OmRvdWJsZSBwcmVjaXNpb24gPSAo dHJ1bmMoKCg2NTg3OTo6ZG91YmxlIHByZWNpc2lvbiAqIHJhbmRvbSgpKSAr IDY2NDg0Ojpkb3VibGUgcHJlY2lzaW9uKSkpKSIKIsKgIC0+wqAgU2VxIFNj YW4gb24gbWVhc3VyZV9kYXRhIG1kwqAgKGNvc3Q9MC4wMC4uMzU2NjgyLjYw IHJvd3M9MjA1NTQ1NjAgd2lkdGg9MjgpIChhY3R1YWwgdGltZT0wLjAxMi4u MTM4NzQuODA5IHJvd3M9MjA1NTQ1NjAgbG9vcHM9MSkiCiLCoCAtPsKgIEhh c2jCoCAoY29zdD01Mi41MC4uNTIuNTAgcm93cz0xMDAwIHdpZHRoPTgpIChh Y3R1YWwgdGltZT0wLjA2Mi4uMC4wNjIgcm93cz0zMCBsb29wcz0xKSIKIsKg wqDCoMKgwqDCoMKgIEJ1Y2tldHM6IDEwMjTCoCBCYXRjaGVzOiAxwqAgTWVt b3J5IFVzYWdlOiAya0IiCiLCoMKgwqDCoMKgwqDCoCAtPsKgIEhhc2hBZ2dy ZWdhdGXCoCAoY29zdD0yMi41MC4uNDIuNTAgcm93cz0xMDAwIHdpZHRoPTAp IChhY3R1YWwgdGltZT0wLjA0OC4uMC4wNTMgcm93cz0zMCBsb29wcz0xKSIK IsKgwqDCoMKgwqDCoMKgwqDCoMKgwqDCoMKgIC0+wqAgRnVuY3Rpb24gU2Nh biBvbiBnZW5lcmF0ZV9zZXJpZXMgc8KgIChjb3N0PTAuMDAuLjIwLjAwIHJv d3M9MTAwMCB3aWR0aD0wKSAoYWN0dWFsIHRpbWU9MC4wMjAuLjAuMDM0IHJv d3M9MzAgbG9vcHM9MSkiCiJUb3RhbCBydW50aW1lOiAxNzE3Ny41MjcgbXMi CgoKIAkJIAkgICAJCSAgCi0tIApTZW50IHZpYSBwZ3NxbC1wZXJmb3JtYW5j ZSBtYWlsaW5nIGxpc3QgKHBnc3FsLXBlcmZvcm1hbmNlQHBvc3RncmVzcWwu b3JnKQpUbyBtYWtlIGNoYW5nZXMgdG8geW91ciBzdWJzY3JpcHRpb246Cmh0 dHA6Ly93d3cucG9zdGdyZXNxbC5vcmcvbWFpbHByZWYvcGdzcWwtcGVyZm9y bWFuY2UK