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Overview
Comment:Minor correct errors in the file format description for FTS3/4 contained in the fts3.c header comment.
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SHA1: fb8aacdd8fbdc946cb271cc589f76b806387937d
User & Date: drh 2012-03-27 00:38:33.806
Context
2012-03-27
13:44
Merge the fts4-incr-merge-exp branch with fts4-incr-merge. (check-in: eb00b95885 user: dan tags: fts4-incr-merge)
11:48
Allow multiple incremental merges to proceed concurrently. This is required to prevent a large crisis-merge from occuring while an even larger incremental-merge is underway. (Closed-Leaf check-in: 7ed9d2f24a user: dan tags: fts4-incr-merge-exp)
00:38
Minor correct errors in the file format description for FTS3/4 contained in the fts3.c header comment. (check-in: fb8aacdd8f user: drh tags: fts4-incr-merge)
00:34
Enhance fts3view to show decodes of segments and doclists. (check-in: 6d09de231b user: drh tags: fts4-incr-merge)
Changes
Unified Diff Ignore Whitespace Patch
Changes to ext/fts3/fts3.c.
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**
** FTS3 used to optionally store character offsets using a compile-time
** option.  But that functionality is no longer supported.
**
** A doclist is stored like this:
**
** array {
**   varint docid;
**   array {                (position list for column 0)
**     varint position;     (2 more than the delta from previous position)
**   }
**   array {
**     varint POS_COLUMN;   (marks start of position list for new column)
**     varint column;       (index of new column)
**     array {








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66
67
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71
72
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**
** FTS3 used to optionally store character offsets using a compile-time
** option.  But that functionality is no longer supported.
**
** A doclist is stored like this:
**
** array {
**   varint docid;          (delta from previous doclist)
**   array {                (position list for column 0)
**     varint position;     (2 more than the delta from previous position)
**   }
**   array {
**     varint POS_COLUMN;   (marks start of position list for new column)
**     varint column;       (index of new column)
**     array {
︙︙
97
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100
101
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109
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111
112

**   value:     123 5 9 1 1 14 35 0 234 72 0
**
** The 123 value is the first docid.  For column zero in this document
** there are two matches at positions 3 and 10 (5-2 and 9-2+3).  The 1
** at D signals the start of a new column; the 1 at E indicates that the
** new column is column number 1.  There are two positions at 12 and 45
** (14-2 and 35-2+12).  The 0 at H indicate the end-of-document.  The
** 234 at I is the next docid.  It has one position 72 (72-2) and then
** terminates with the 0 at K.
**
** A "position-list" is the list of positions for multiple columns for
** a single docid.  A "column-list" is the set of positions for a single
** column.  Hence, a position-list consists of one or more column-lists,
** a document record consists of a docid followed by a position-list and
** a doclist consists of one or more document records.
**








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|








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**   value:     123 5 9 1 1 14 35 0 234 72 0
**
** The 123 value is the first docid.  For column zero in this document
** there are two matches at positions 3 and 10 (5-2 and 9-2+3).  The 1
** at D signals the start of a new column; the 1 at E indicates that the
** new column is column number 1.  There are two positions at 12 and 45
** (14-2 and 35-2+12).  The 0 at H indicate the end-of-document.  The
** 234 at I is the delta to next docid (357).  It has one position 70
** (72-2) and then terminates with the 0 at K.
**
** A "position-list" is the list of positions for multiple columns for
** a single docid.  A "column-list" is the set of positions for a single
** column.  Hence, a position-list consists of one or more column-lists,
** a document record consists of a docid followed by a position-list and
** a doclist consists of one or more document records.
**
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