[sql] Import SQLite 3.17.0.

third_party/sqlite/src/ext/fts5/fts5.h

 /*
 ** 2014 May 31
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
 **
 **    May you do good and not evil.
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
@@ skipping 66 matching lines @@
 **   If parameter iCol is less than zero, set output variable *pnToken
 **   to the total number of tokens in the current row. Or, if iCol is
 **   non-negative but less than the number of columns in the table, set
 **   *pnToken to the number of tokens in column iCol of the current row.
 **
 **   If parameter iCol is greater than or equal to the number of columns
 **   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
 **   an OOM condition or IO error), an appropriate SQLite error code is 
 **   returned.
 **
+**   This function may be quite inefficient if used with an FTS5 table
+**   created with the "columnsize=0" option.
+**
 ** xColumnText:
 **   This function attempts to retrieve the text of column iCol of the
 **   current document. If successful, (*pz) is set to point to a buffer
 **   containing the text in utf-8 encoding, (*pn) is set to the size in bytes
 **   (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
 **   if an error occurs, an SQLite error code is returned and the final values
 **   of (*pz) and (*pn) are undefined.
 **
 ** xPhraseCount:
 **   Returns the number of phrases in the current query expression.
 **
 ** xPhraseSize:
 **   Returns the number of tokens in phrase iPhrase of the query. Phrases
 **   are numbered starting from zero.
 **
 ** xInstCount:
 **   Set *pnInst to the total number of occurrences of all phrases within
 **   the query within the current row. Return SQLITE_OK if successful, or
 **   an error code (i.e. SQLITE_NOMEM) if an error occurs.
 **
+**   This API can be quite slow if used with an FTS5 table created with the
+**   "detail=none" or "detail=column" option. If the FTS5 table is created 
+**   with either "detail=none" or "detail=column" and "content=" option 
+**   (i.e. if it is a contentless table), then this API always returns 0.
+**
 ** xInst:
 **   Query for the details of phrase match iIdx within the current row.
 **   Phrase matches are numbered starting from zero, so the iIdx argument
 **   should be greater than or equal to zero and smaller than the value
 **   output by xInstCount().
 **
+**   Usually, output parameter *piPhrase is set to the phrase number, *piCol
+**   to the column in which it occurs and *piOff the token offset of the
+**   first token of the phrase. The exception is if the table was created
+**   with the offsets=0 option specified. In this case *piOff is always
+**   set to -1.
+**
 **   Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM) 
 **   if an error occurs.
 **
+**   This API can be quite slow if used with an FTS5 table created with the
+**   "detail=none" or "detail=column" option. 
+**
 ** xRowid:
 **   Returns the rowid of the current row.
 **
 ** xTokenize:
 **   Tokenize text using the tokenizer belonging to the FTS5 table.
 **
 ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
 **   This API function is used to query the FTS table for phrase iPhrase
 **   of the current query. Specifically, a query equivalent to:
 **
 **       ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
 **
 **   with $p set to a phrase equivalent to the phrase iPhrase of the
-**   current query is executed. For each row visited, the callback function
-**   passed as the fourth argument is invoked. The context and API objects 
-**   passed to the callback function may be used to access the properties of
-**   each matched row. Invoking Api.xUserData() returns a copy of the pointer
-**   passed as the third argument to pUserData.
+**   current query is executed. Any column filter that applies to
+**   phrase iPhrase of the current query is included in $p. For each 
+**   row visited, the callback function passed as the fourth argument 
+**   is invoked. The context and API objects passed to the callback 
+**   function may be used to access the properties of each matched row.
+**   Invoking Api.xUserData() returns a copy of the pointer passed as 
+**   the third argument to pUserData.
 **
 **   If the callback function returns any value other than SQLITE_OK, the
 **   query is abandoned and the xQueryPhrase function returns immediately.
 **   If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
 **   Otherwise, the error code is propagated upwards.
 **
 **   If the query runs to completion without incident, SQLITE_OK is returned.
 **   Or, if some error occurs before the query completes or is aborted by
 **   the callback, an SQLite error code is returned.
 **
@@ skipping 45 matching lines @@
 **   This function is used, along with type Fts5PhraseIter and the xPhraseNext
 **   method, to iterate through all instances of a single query phrase within
 **   the current row. This is the same information as is accessible via the
 **   xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
 **   to use, this API may be faster under some circumstances. To iterate 
 **   through instances of phrase iPhrase, use the following code:
 **
 **       Fts5PhraseIter iter;
 **       int iCol, iOff;
 **       for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
-**           iOff>=0;
+**           iCol>=0;
 **           pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
 **       ){
 **         // An instance of phrase iPhrase at offset iOff of column iCol
 **       }
 **
 **   The Fts5PhraseIter structure is defined above. Applications should not
 **   modify this structure directly - it should only be used as shown above
-**   with the xPhraseFirst() and xPhraseNext() API methods.
+**   with the xPhraseFirst() and xPhraseNext() API methods (and by
+**   xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
+**
+**   This API can be quite slow if used with an FTS5 table created with the
+**   "detail=none" or "detail=column" option. If the FTS5 table is created 
+**   with either "detail=none" or "detail=column" and "content=" option 
+**   (i.e. if it is a contentless table), then this API always iterates
+**   through an empty set (all calls to xPhraseFirst() set iCol to -1).
 **
 ** xPhraseNext()
 **   See xPhraseFirst above.
+**
+** xPhraseFirstColumn()
+**   This function and xPhraseNextColumn() are similar to the xPhraseFirst()
+**   and xPhraseNext() APIs described above. The difference is that instead
+**   of iterating through all instances of a phrase in the current row, these
+**   APIs are used to iterate through the set of columns in the current row
+**   that contain one or more instances of a specified phrase. For example:
+**
+**       Fts5PhraseIter iter;
+**       int iCol;
+**       for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
+**           iCol>=0;
+**           pApi->xPhraseNextColumn(pFts, &iter, &iCol)
+**       ){
+**         // Column iCol contains at least one instance of phrase iPhrase
+**       }
+**
+**   This API can be quite slow if used with an FTS5 table created with the
+**   "detail=none" option. If the FTS5 table is created with either 
+**   "detail=none" "content=" option (i.e. if it is a contentless table), 
+**   then this API always iterates through an empty set (all calls to 
+**   xPhraseFirstColumn() set iCol to -1).
+**
+**   The information accessed using this API and its companion
+**   xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
+**   (or xInst/xInstCount). The chief advantage of this API is that it is
+**   significantly more efficient than those alternatives when used with
+**   "detail=column" tables.  
+**
+** xPhraseNextColumn()
+**   See xPhraseFirstColumn above.
 */
 struct Fts5ExtensionApi {
-  int iVersion;                   /* Currently always set to 1 */
+  int iVersion;                   /* Currently always set to 3 */
 
   void *(*xUserData)(Fts5Context*);
 
   int (*xColumnCount)(Fts5Context*);
   int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
   int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
 
   int (*xTokenize)(Fts5Context*, 
     const char *pText, int nText, /* Text to tokenize */
     void *pCtx,                   /* Context passed to xToken() */
     int (*xToken)(void*, int, const char*, int, int, int)       /* Callback */
   );
 
   int (*xPhraseCount)(Fts5Context*);
   int (*xPhraseSize)(Fts5Context*, int iPhrase);
 
   int (*xInstCount)(Fts5Context*, int *pnInst);
   int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
 
   sqlite3_int64 (*xRowid)(Fts5Context*);
   int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
   int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
 
   int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
     int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
   );
   int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
   void *(*xGetAuxdata)(Fts5Context*, int bClear);
 
-  void (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
+  int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
   void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
+
+  int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
+  void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
 };
 
 /* 
 ** CUSTOM AUXILIARY FUNCTIONS
 *************************************************************************/
 
 /*************************************************************************
 ** CUSTOM TOKENIZERS
 **
 ** Applications may also register custom tokenizer types. A tokenizer 
 ** is registered by providing fts5 with a populated instance of the 
 ** following structure. All structure methods must be defined, setting
 ** any member of the fts5_tokenizer struct to NULL leads to undefined
 ** behaviour. The structure methods are expected to function as follows:
 **
 ** xCreate:
-**   This function is used to allocate and inititalize a tokenizer instance.
+**   This function is used to allocate and initialize a tokenizer instance.
 **   A tokenizer instance is required to actually tokenize text.
 **
 **   The first argument passed to this function is a copy of the (void*)
 **   pointer provided by the application when the fts5_tokenizer object
 **   was registered with FTS5 (the third argument to xCreateTokenizer()). 
 **   The second and third arguments are an array of nul-terminated strings
 **   containing the tokenizer arguments, if any, specified following the
 **   tokenizer name as part of the CREATE VIRTUAL TABLE statement used
 **   to create the FTS5 table.
 **
@@ skipping 238 matching lines @@
 
 /*
 ** END OF REGISTRATION API
 *************************************************************************/
 
 #ifdef __cplusplus
 }  /* end of the 'extern "C"' block */
 #endif
 
 #endif /* _FTS5_H */
-