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Comment:Update fts3 documentation to mention that fts3_tokenzer(x,y) is only available if SQLITE_ENABLE_FTS3_TOKENIZER is defined at compile time.
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SHA1: 27ee6d023315774f4dd803799b068b09302c708d
User & Date: dan 2016-02-08 19:55:42
Context
2016-02-09
14:43
Update the 3.11.0 change log. check-in: 0dc9452382 user: drh tags: trunk
2016-02-08
19:55
Update fts3 documentation to mention that fts3_tokenzer(x,y) is only available if SQLITE_ENABLE_FTS3_TOKENIZER is defined at compile time. check-in: 27ee6d0233 user: dan tags: trunk
2016-02-03
19:47
Update the documentation for PRAGMA synchronous=EXTRA. check-in: bcf687da9c user: drh tags: trunk
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Changes to pages/fts3.in.

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  case-sensitive. In the example above, specifying that "X" is a separator
  character does not affect the way "x" is handled.

<h2>Custom (User Implemented) Tokenizers</h2>

<p>
  As well as the built-in "simple", "porter" and (possibly) "icu" and
  "unicode61" tokenizers,







  FTS exports an interface that allows users to implement custom tokenizers
  using C. The interface used to create a new tokenizer is defined and 
  described in the fts3_tokenizer.h source file.

<p>
  Registering a new FTS tokenizer is similar to registering a new
  virtual table module with SQLite. The user passes a pointer to a
  structure containing pointers to various callback functions that
  make up the implementation of the new tokenizer type. For tokenizers,
  the structure (defined in fts3_tokenizer.h) is called
................................................................................
  it is registered as tokenizer &lt;tokenizer-name&gt; and a copy of it
  returned. If only one argument is passed, a pointer to the tokenizer
  implementation currently registered as &lt;tokenizer-name&gt; is returned,
  encoded as a blob. Or, if no such tokenizer exists, an SQL exception
  (error) is raised.

<p>






  <b>SECURITY WARNING</b>: If the fts3/4 extension is used in an environment


  where potentially malicious users may execute arbitrary SQL, they should 
  be prevented from invoking the fts3_tokenizer() function, possibly using 
  the [sqlite3_set_authorizer()|authorization callback].

<p>
  The following block contains an example of calling the fts3_tokenizer()
  function from C code:

<codeblock>
  <i>/*







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  case-sensitive. In the example above, specifying that "X" is a separator
  character does not affect the way "x" is handled.

<h2>Custom (User Implemented) Tokenizers</h2>

<p>
  As well as the built-in "simple", "porter" and (possibly) "icu" and
  "unicode61" tokenizers, if the library is compiled with the following 
  compiler option:

<codeblock>
  -DSQLITE_ENABLE_FTS3_TOKENIZER
</codeblock>

<p>
  then FTS exports an interface that allows users to implement custom
  tokenizers using C. The interface used to create a new tokenizer is defined
  and described in the fts3_tokenizer.h source file.

<p>
  Registering a new FTS tokenizer is similar to registering a new
  virtual table module with SQLite. The user passes a pointer to a
  structure containing pointers to various callback functions that
  make up the implementation of the new tokenizer type. For tokenizers,
  the structure (defined in fts3_tokenizer.h) is called
................................................................................
  it is registered as tokenizer &lt;tokenizer-name&gt; and a copy of it
  returned. If only one argument is passed, a pointer to the tokenizer
  implementation currently registered as &lt;tokenizer-name&gt; is returned,
  encoded as a blob. Or, if no such tokenizer exists, an SQL exception
  (error) is raised.

<p>
  As of SQLite version 3.11.0, the second form of the fts3_tokenizer() function
  is only available if the library is compiled with the
  -DSQLITE_ENABLE_FTS3_TOKENIZER compiler switch. In earlier versions it was
  always available.

<p>
  <b>SECURITY WARNING</b>: 
  If a version of the fts3/4 extension that supports the second form of
  fts3_tokenizer() is deployed in an environment where potentially malicious
  users may execute arbitrary SQL, they should be prevented from invoking the
  fts3_tokenizer() function, possibly using the 
  [sqlite3_set_authorizer()|authorization callback].

<p>
  The following block contains an example of calling the fts3_tokenizer()
  function from C code:

<codeblock>
  <i>/*