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Overview
Comment:Add missing parenthesis to an expression in fts3.html.
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SHA1: d366268bab815a5575855d708c55da8151906e1d
User & Date: dan 2015-09-02 11:30:35
Context
2015-09-07
10:53
Fix two typos. check-in: 0506240273 user: drh tags: trunk
2015-09-02
11:30
Add missing parenthesis to an expression in fts3.html. check-in: d366268bab user: dan tags: trunk
2015-08-28
18:13
Improved explanation of how to build the command-line shell on the howtocompile.html page. check-in: 501ee3f88e user: drh tags: trunk
Changes
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Changes to pages/fts3.in.

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<pre>
          hits_for_phrase_p_column_c  = array&#91;c + p*cols&#93;
</pre>
      For queries that use OR expressions, or those that use LIMIT or return
      many rows, the 'y' matchinfo option may be faster than 'x'.

<tr><td>b<td style="white-space:nowrap"><i>(cols+31)/32</i> * <i>phrases</i> 
<td><tcl>hd_fragment matchinfo-b {matchinfo b flag}</tcl>

  The matchinfo 'b' flag provides similar information to the
  [matchinfo 'y' flag], but in a more
  compact form. Instead of the precise number of hits, 'b' provides a single
  boolean flag for each phrase/column combination. If the phrase is present in
  the column at least once (i.e. if the corresponding integer output of 'y' would
................................................................................
  contains data for phrase 0 and columns 32-44, and so on.

<p style="margin-left:0;margin-right:0">
  For example, if nCol is the number of columns in the table, to determine if
  phrase p is present in column c:

<pre>
    p_is_in_c = array&#91;p * (nCol+31)/32&#93; & (1 &lt;&lt; (c % 32))
</pre>

  <tr><td>n <td>1 <td>The number of rows in the FTS4 table. This value is
    only available when querying FTS4 tables, not FTS3.
  <tr><td>a <td><i>cols</i> <td>For each column, the average number of
    tokens in the text values stored in the column (considering all rows in
    the FTS4 table). This value is only available when querying FTS4 tables,







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1165
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....
1194
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1200
1201
1202
1203
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<pre>
          hits_for_phrase_p_column_c  = array&#91;c + p*cols&#93;
</pre>
      For queries that use OR expressions, or those that use LIMIT or return
      many rows, the 'y' matchinfo option may be faster than 'x'.

<tr><td>b<td style="white-space:nowrap"><i>((cols+31)/32)</i> * <i>phrases</i> 
<td><tcl>hd_fragment matchinfo-b {matchinfo b flag}</tcl>

  The matchinfo 'b' flag provides similar information to the
  [matchinfo 'y' flag], but in a more
  compact form. Instead of the precise number of hits, 'b' provides a single
  boolean flag for each phrase/column combination. If the phrase is present in
  the column at least once (i.e. if the corresponding integer output of 'y' would
................................................................................
  contains data for phrase 0 and columns 32-44, and so on.

<p style="margin-left:0;margin-right:0">
  For example, if nCol is the number of columns in the table, to determine if
  phrase p is present in column c:

<pre>
    p_is_in_c = array&#91;p * ((nCol+31)/32)&#93; & (1 &lt;&lt; (c % 32))
</pre>

  <tr><td>n <td>1 <td>The number of rows in the FTS4 table. This value is
    only available when querying FTS4 tables, not FTS3.
  <tr><td>a <td><i>cols</i> <td>For each column, the average number of
    tokens in the text values stored in the column (considering all rows in
    the FTS4 table). This value is only available when querying FTS4 tables,