Add comments to window.c describing how other window frames will be implemented.

FossilOrigin-Name: 16168146b202915252f9375aef38e65ca20c5d4aa906e851d4d3a484db57562d

manifest

@@ -1,5 +1,5 @@
-C Begin\sadding\ssupport\sfor\smore\sesoteric\swindow\sframes.
-D 2018-05-21T19:45:11.880
+C Add\scomments\sto\swindow.c\sdescribing\show\sother\swindow\sframes\swill\sbe\simplemented.
+D 2018-05-22T20:35:37.079
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F Makefile.in bfc40f350586923e0419d2ea4b559c37ec10ee4b6e210e08c14401f8e340f0da
@@ -581,7 +581,7 @@ F src/where.c 60ec752fcbe9f9e0271ac60548d159a540a1ee47a4f9fedc85e88a3d0e392dd1
 F src/whereInt.h cbae2bcd37cfebdb7812a8b188cdb19634ced2b9346470d1c270556b0c33ea53
 F src/wherecode.c 728c7f70731430ccdac807a79969873e1af6968bf1c4745dff3f9dd35f636cc8
 F src/whereexpr.c e90b2e76dcabc81edff56633bf281bc01d93b71e0c81482dc06925ce39f5844a
-F src/window.c da24f2e57a704dd8e0ce96df18e7442145582c65b4eb1c3176367e530d665928
+F src/window.c 37eb02c2af935f207ba902ef25ec27d635b68bb1567f9e5994a6720bac1c093e
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test a6d901b436328bd67a79b41bb0ac2663918fe3bd
 F test/affinity3.test 6a101af2fc945ce2912f6fe54dd646018551710d
@@ -1614,8 +1614,8 @@ F test/win32lock.test fbf107c91d8f5512be5a5b87c4c42ab9fdd54972
 F test/win32longpath.test 169c75a3b2e43481f4a62122510210c67b08f26d
 F test/win32nolock.test ac4f08811a562e45a5755e661f45ca85892bdbbc
 F test/window1.test 5705337783d220b47f6fb4432264543b7557a05be8013d772f57d71f2fded271
-F test/window2.tcl 19a7d45c4502f00917649a171a4eb1da3670657f5cb102bce7a813e15a112b3f
-F test/window2.test 23daf252647d780f046a2e612d7f0492d4fe589b3302fd6c062b0abfff3743bf
+F test/window2.tcl 7e0b692974a18ae0992dd2e76be83d8e1c6c5cac3190d84fa62911ab0e5c7896
+F test/window2.test e1453371b605e54eeb2264fc3a4a23c5eba93e95f6c7f3230fce9d34b4b5e8a4
 F test/with1.test 58475190cd8caaeebea8cfeb2a264ec97a0c492b8ffe9ad20cefbb23df462f96
 F test/with2.test e0030e2f0267a910d6c0e4f46f2dfe941c1cc0d4f659ba69b3597728e7e8f1ab
 F test/with3.test 5e8ce2c585170bbbc0544e2a01a4941fa0be173ba5265e5c92eb588cd99a232d
@@ -1732,7 +1732,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 19c2e4b2f164521eab84cb0a0e12984be9431eaedd001dd3671e9ea1a6212353
-R 977b49583a548e1f3f37fbf1de8b5833
+P bc4b81d60d40583de0f929730159011c1a7696802532ebd02220de3ace94a60d
+R b67e8a3ce976e7ed7840f10e74d98764
 U dan
-Z 314fa758fa6aadc36a0f111ad4e55744
+Z 023d577304fe302f9eee3398820219e9

manifest.uuid

@@ -1 +1 @@
-bc4b81d60d40583de0f929730159011c1a7696802532ebd02220de3ace94a60d
+16168146b202915252f9375aef38e65ca20c5d4aa906e851d4d3a484db57562d

src/window.c

@@ -155,21 +155,87 @@ void sqlite3WindowCodeInit(Parse *pParse, Window *pWin){
 **
 **========================================================================
 **
-** ROWS BETWEEN UNBOUNDED PRECEDING AND <expr> PRECEDING
-** ROWS BETWEEN <expr> PRECEDING    AND <expr> PRECEDING
-** ROWS BETWEEN <expr> PRECEDING    AND CURRENT ROW
-** ROWS BETWEEN UNBOUNDED PRECEDING AND <expr> FOLLOWING
 ** ROWS BETWEEN <expr> PRECEDING    AND <expr> FOLLOWING
-** ROWS BETWEEN CURRENT ROW         AND <expr> FOLLOWING
-** ROWS BETWEEN <expr> FOLLOWING    AND <expr> FOLLOWING
-** ROWS BETWEEN <expr> PRECEDING    AND UNBOUNDED FOLLOWING
-** ROWS BETWEEN <expr> FOLLOWING    AND UNBOUNDED FOLLOWING
-**
-**   Cases that involve <expr> PRECEDING or <expr> FOLLOWING.
 **
 **   ...
+**     if( new partition ){
+**       Gosub flush_partition
+**     }
 **     Insert (record in eph-table)
 **   sqlite3WhereEnd()
+**   Gosub flush_partition
+**
+** flush_partition:
+**   OpenDup (csr -> csr2)
+**   OpenDup (csr -> csr3)
+**   regPrec = <expr1>            // PRECEDING expression
+**   regFollow = <expr2>          // FOLLOWING expression
+**   if( regPrec<0 || regFollow<0 ) throw exception!
+**   Rewind (csr,csr2,csr3)       // if EOF goto flush_partition_done
+**     Aggstep (csr3)
+**     Next(csr3)                 // if EOF fall-through
+**     if( (regFollow--)<=0 ){
+**       AggFinal (xValue)
+**       Gosub addrGosub
+**       Next(csr)                // if EOF goto flush_partition_done
+**       if( (regPrec--)<=0 ){
+**         AggStep (csr2, xInverse)
+**         Next(csr2)
+**       }
+**     }
+** flush_partition_done:
+**   Close (csr2)
+**   Close (csr3)
+**   ResetSorter (csr)
+**   Return
+**
+** ROWS BETWEEN <expr> PRECEDING    AND CURRENT ROW
+** ROWS BETWEEN CURRENT ROW         AND <expr> FOLLOWING
+** ROWS BETWEEN <expr> PRECEDING    AND UNBOUNDED FOLLOWING
+** ROWS BETWEEN UNBOUNDED PRECEDING AND <expr> FOLLOWING
+**
+**   These are similar to the above. For "CURRENT ROW", intialize the
+**   register to 0. For "UNBOUNDED ..." to infinity.
+**
+** ROWS BETWEEN <expr> PRECEDING    AND <expr> PRECEDING
+**
+**   Replace the bit after "Rewind" in the above with:
+**
+**     if( (regFollow--)<=0 ){
+**       AggStep (csr3)
+**       Next (csr3)
+**     }
+**     AggFinal (xValue)
+**     Gosub addrGosub
+**     Next(csr)                  // if EOF goto flush_partition_done
+**     if( (regPrec--)<=0 ){
+**       AggStep (csr2, xInverse)
+**       Next (csr2)
+**     }
+**
+** ROWS BETWEEN <expr> FOLLOWING    AND <expr> FOLLOWING
+**
+**   regFollow = regFollow - regPrec
+**   Rewind (csr,csr2,csr3)       // if EOF goto flush_partition_done
+**     Aggstep (csr3)
+**     Next(csr3)                 // if EOF fall-through
+**     if( (regFollow--)<=0 ){
+**       AggStep (csr2, xInverse)
+**       Next (csr2)
+**       if( (regPrec--)<=0 ){
+**         AggFinal (xValue)
+**         Gosub addrGosub
+**         Next(csr)              // if EOF goto flush_partition_done
+**       }
+**     }
+**
+** ROWS BETWEEN UNBOUNDED PRECEDING AND <expr> PRECEDING
+** ROWS BETWEEN <expr> FOLLOWING    AND UNBOUNDED FOLLOWING
+**
+**   Similar to the above, except with regPrec or regFollow set to infinity,
+**   as appropriate.
+**
+**
 **
 */
 void sqlite3WindowCodeStep(

test/window2.tcl

@@ -160,6 +160,20 @@ execsql_test 2.3 {
   ) FROM t1
 }
 
+execsql_test 2.4 {
+  SELECT a, sum(d) OVER (
+    ORDER BY d
+    ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING
+  ) FROM t1
+}
+
+execsql_test 2.5 {
+  SELECT a, sum(d) OVER (
+    ORDER BY d
+    ROWS BETWEEN 1 PRECEDING AND 1 PRECEDING
+  ) FROM t1
+}
+
 finish_test
 
 

test/window2.test

@@ -66,4 +66,18 @@ do_execsql_test 2.3 {
   ) FROM t1
 } {1 21   2 21   3 21   4 21   5 21   6 21}
 
+do_execsql_test 2.4 {
+  SELECT a, sum(d) OVER (
+    ORDER BY d
+    ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING
+  ) FROM t1
+} {1 3   2 6   3 9   4 12   5 15   6 11}
+
+do_execsql_test 2.5 {
+  SELECT a, sum(d) OVER (
+    ORDER BY d
+    ROWS BETWEEN 1 PRECEDING AND 1 PRECEDING
+  ) FROM t1
+} {1 {}   2 1   3 2   4 3   5 4   6 5}
+
 finish_test