From d75e03df2b668d78adbd54390bbd6d12c7af56ba Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Tue, 3 Oct 2006 11:42:28 +0000
Subject: [PATCH] Add the option to omit offset information from posting lists
 in FTS1. (CVS 3456)

FossilOrigin-Name: fdcea7b1ffd821f3f2b6d30997d3957f705a6d0c
---
 ext/fts1/fts1.c | 52 +++++++++++++++++++++++++++++++++++--------------
 manifest        | 12 ++++++------
 manifest.uuid   |  2 +-
 3 files changed, 44 insertions(+), 22 deletions(-)

diff --git a/ext/fts1/fts1.c b/ext/fts1/fts1.c
index 24c6ec40d3..e62aec1cc5 100644
--- a/ext/fts1/fts1.c
+++ b/ext/fts1/fts1.c
@@ -179,6 +179,18 @@ typedef enum DocListType {
   DL_POSITIONS_OFFSETS    /* docids + positions + offsets */
 } DocListType;
 
+/*
+** By default, positions and offsets are stored in the doclists.
+** To change this so that only positions are stored, compile
+** with
+**
+**          -DDL_DEFAULT=DL_POSITIONS
+**
+*/
+#ifndef DL_DEFAULT
+# define DL_DEFAULT DL_POSITIONS_OFFSETS
+#endif
+
 typedef struct DocList {
   char *pData;
   int nData;
@@ -273,18 +285,28 @@ static void docListAddPos(DocList *d, int iColumn, int iPos){
   appendVarint(d, POS_END);  /* add new terminator */
 }
 
-static void docListAddPosOffset(DocList *d, int iColumn, int iPos,
-                                int iStartOffset, int iEndOffset){
-  assert( d->iType==DL_POSITIONS_OFFSETS );
+/*
+** Add a position and starting and ending offsets to a doclist.
+**
+** If the doclist is setup to handle only positions, then insert
+** the position only and ignore the offsets.
+*/
+static void docListAddPosOffset(
+  DocList *d,             /* Doclist under construction */
+  int iColumn,            /* Column the inserted term is part of */
+  int iPos,               /* Position of the inserted term */
+  int iStartOffset,       /* Starting offset of inserted term */
+  int iEndOffset          /* Ending offset of inserted term */
+){
+  assert( d->iType>=DL_POSITIONS );
   addPos(d, iColumn, iPos);
-
-  assert( iStartOffset>=d->iLastOffset );
-  appendVarint(d, iStartOffset-d->iLastOffset);
-  d->iLastOffset = iStartOffset;
-
-  assert( iEndOffset>=iStartOffset );
-  appendVarint(d, iEndOffset-iStartOffset);
-
+  if( d->iType==DL_POSITIONS_OFFSETS ){
+    assert( iStartOffset>=d->iLastOffset );
+    appendVarint(d, iStartOffset-d->iLastOffset);
+    d->iLastOffset = iStartOffset;
+    assert( iEndOffset>=iStartOffset );
+    appendVarint(d, iEndOffset-iStartOffset);
+  }
   appendVarint(d, POS_END);  /* add new terminator */
 }
 
@@ -1299,7 +1321,7 @@ static int term_select(fulltext_vtab *v, const char *pTerm, int nTerm,
   if( rc!=SQLITE_ROW ) return rc;
 
   *rowid = sqlite3_column_int64(s, 0);
-  docListInit(out, DL_POSITIONS_OFFSETS,
+  docListInit(out, DL_DEFAULT,
               sqlite3_column_blob(s, 1), sqlite3_column_bytes(s, 1));
 
   /* We expect only one row.  We must execute another sqlite3_step()
@@ -1334,7 +1356,7 @@ static int term_select_all(
   rc = sqlite3_bind_text(s, 1, pTerm, nTerm, SQLITE_STATIC);
   if( rc!=SQLITE_OK ) return rc;
 
-  docListInit(&doclist, DL_POSITIONS_OFFSETS, 0, 0);
+  docListInit(&doclist, DL_DEFAULT, 0, 0);
 
   /* TODO(shess) Handle schema and busy errors. */
   while( (rc=sql_step_statement(v, TERM_SELECT_ALL_STMT, &s))==SQLITE_ROW ){
@@ -2917,7 +2939,7 @@ static int buildTerms(fulltext_vtab *v, fts1Hash *terms, sqlite_int64 iDocid,
 
     p = fts1HashFind(terms, pToken, nTokenBytes);
     if( p==NULL ){
-      p = docListNew(DL_POSITIONS_OFFSETS);
+      p = docListNew(DL_DEFAULT);
       docListAddDocid(p, iDocid);
       fts1HashInsert(terms, pToken, nTokenBytes, p);
     }
@@ -2944,7 +2966,7 @@ static int index_insert_term(fulltext_vtab *v, const char *pTerm, int nTerm,
 
   rc = term_select(v, pTerm, nTerm, iSegment, &iIndexRow, &doclist);
   if( rc==SQLITE_DONE ){
-    docListInit(&doclist, DL_POSITIONS_OFFSETS, 0, 0);
+    docListInit(&doclist, DL_DEFAULT, 0, 0);
     docListUpdate(&doclist, d);
     /* TODO(shess) Consider length(doclist)>CHUNK_MAX? */
     rc = term_insert(v, NULL, pTerm, nTerm, iSegment, &doclist);
diff --git a/manifest b/manifest
index 3122aa213b..fe803e17de 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Another\stypo\sin\sthe\sPorter\sstemmer\scheck-in.\s(CVS\s3455)
-D 2006-10-01T20:41:03
+C Add\sthe\soption\sto\somit\soffset\sinformation\sfrom\sposting\slists\sin\sFTS1.\s(CVS\s3456)
+D 2006-10-03T11:42:29
 F Makefile.in cabd42d34340f49260bc2a7668c38eba8d4cfd99
 F Makefile.linux-gcc 2d8574d1ba75f129aba2019f0b959db380a90935
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -21,7 +21,7 @@ F ext/README.txt 913a7bd3f4837ab14d7e063304181787658b14e1
 F ext/fts1/README.txt 20ac73b006a70bcfd80069bdaf59214b6cf1db5e
 F ext/fts1/ft_hash.c 3927bd880e65329bdc6f506555b228b28924921b
 F ext/fts1/ft_hash.h 1a35e654a235c2c662d3ca0dfc3138ad60b8b7d5
-F ext/fts1/fts1.c 4f6278a61dd57a2ead405188eb847b3f682850e3
+F ext/fts1/fts1.c 302d4fa00d5e3b1da0518c0b7f648d7cded900d0
 F ext/fts1/fts1.h 6060b8f62c1d925ea8356cb1a6598073eb9159a6
 F ext/fts1/fts1_hash.c 3196cee866edbebb1c0521e21672e6d599965114
 F ext/fts1/fts1_hash.h 957d378355ed29f672cd5add012ce8b088a5e089
@@ -402,7 +402,7 @@ F www/tclsqlite.tcl bb0d1357328a42b1993d78573e587c6dcbc964b9
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl 97e2b5cd296f7d8057e11f44427dea8a4c2db513
-P a7350bf86c41c428adbfe42dc9cbb3ecf0045c25
-R e8fc3b6778614d67cb9408a9cd7f6faa
+P 6696bda11ccad9663b15206592116d638aa3ff0a
+R c692c93a2339c5abd4c2802c5af8a551
 U drh
-Z f4756b3a2eb03f159a028654e46fb528
+Z 8d253c126c0d6e27101f1f52b6f86a2d
diff --git a/manifest.uuid b/manifest.uuid
index 09a7f3d20f..e2f2161b33 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-6696bda11ccad9663b15206592116d638aa3ff0a
\ No newline at end of file
+fdcea7b1ffd821f3f2b6d30997d3957f705a6d0c
\ No newline at end of file