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Overview
Comment: | Update comments in fts3_snippet.c. |
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Timelines: | family | ancestors | descendants | both | trunk |
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dd9689b7c31861484f8d8062478ae73d |
User & Date: | dan 2010-01-12 17:57:30.000 |
Context
2010-01-12
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19:28 | Fix the implementation of CURRENT_TIMESTAME and CURRENT_DATE when SQLITE_OMIT_DATETIME_FUNCS is defined. (check-in: eb98265b59 user: drh tags: trunk) | |
17:57 | Update comments in fts3_snippet.c. (check-in: dd9689b7c3 user: dan tags: trunk) | |
17:04 | Use #ifdefs to disable unused code when SQLITE_OMIT_FLOATING_POINT is defined. (check-in: 66bab85619 user: drh tags: trunk) | |
Changes
Changes to ext/fts3/fts3_snippet.c.
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14 15 16 17 18 19 20 | #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) #include "fts3Int.h" #include <string.h> #include <assert.h> #include <ctype.h> | | > > > > > > > > > > | > > > > > > > | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | | > | 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 | #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) #include "fts3Int.h" #include <string.h> #include <assert.h> #include <ctype.h> /* ** Used as an fts3ExprIterate() context when loading phrase doclists to ** Fts3Expr.aDoclist[]/nDoclist. */ typedef struct LoadDoclistCtx LoadDoclistCtx; struct LoadDoclistCtx { Fts3Table *pTab; /* FTS3 Table */ int nPhrase; /* Number of phrases seen so far */ int nToken; /* Number of tokens seen so far */ }; /* ** The following types are used as part of the implementation of the ** fts3BestSnippet() routine. */ typedef struct SnippetIter SnippetIter; typedef struct SnippetPhrase SnippetPhrase; typedef struct SnippetFragment SnippetFragment; struct SnippetIter { Fts3Cursor *pCsr; /* Cursor snippet is being generated from */ int iCol; /* Extract snippet from this column */ int nSnippet; /* Requested snippet length (in tokens) */ int nPhrase; /* Number of phrases in query */ SnippetPhrase *aPhrase; /* Array of size nPhrase */ int iCurrent; /* First token of current snippet */ }; struct SnippetPhrase { int nToken; /* Number of tokens in phrase */ char *pList; /* Pointer to start of phrase position list */ int iHead; /* Next value in position list */ char *pHead; /* Position list data following iHead */ int iTail; /* Next value in trailing position list */ char *pTail; /* Position list data following iTail */ }; struct SnippetFragment { int iCol; /* Column snippet is extracted from */ int iPos; /* Index of first token in snippet */ u64 covered; /* Mask of query phrases covered */ u64 hlmask; /* Mask of snippet terms to highlight */ }; /* ** This type is used as an fts3ExprIterate() context object while ** accumulating the data returned by the matchinfo() function. */ typedef struct MatchInfo MatchInfo; struct MatchInfo { Fts3Cursor *pCursor; /* FTS3 Cursor */ int nCol; /* Number of columns in table */ u32 *aMatchinfo; /* Pre-allocated buffer */ }; /* ** The snippet() and offsets() functions both return text values. An instance ** of the following structure is used to accumulate those values while the ** functions are running. See fts3StringAppend() for details. */ typedef struct StrBuffer StrBuffer; struct StrBuffer { char *z; /* Pointer to buffer containing string */ int n; /* Length of z in bytes (excl. nul-term) */ int nAlloc; /* Allocated size of buffer z in bytes */ }; /* ** This function is used to help iterate through a position-list. A position ** list is a list of unique integers, sorted from smallest to largest. Each ** element of the list is represented by an FTS3 varint that takes the value ** of the difference between the current element and the previous one plus ** two. For example, to store the position-list: ** ** 4 9 113 ** ** the three varints: ** ** 6 7 106 ** ** are encoded. ** ** When this function is called, *pp points to the start of an element of ** the list. *piPos contains the value of the previous entry in the list. ** After it returns, *piPos contains the value of the next element of the ** list and *pp is advanced to the following varint. */ static void fts3GetDeltaPosition(char **pp, int *piPos){ int iVal; *pp += sqlite3Fts3GetVarint32(*pp, &iVal); *piPos += (iVal-2); } /* ** Helper function for fts3ExprIterate() (see below). */ static int fts3ExprIterate2( Fts3Expr *pExpr, /* Expression to iterate phrases of */ int *piPhrase, /* Pointer to phrase counter */ int (*x)(Fts3Expr*,int,void*), /* Callback function to invoke for phrases */ void *pCtx /* Second argument to pass to callback */ ){ int rc; /* Return code */ int eType = pExpr->eType; /* Type of expression node pExpr */ if( eType!=FTSQUERY_PHRASE ){ assert( pExpr->pLeft && pExpr->pRight ); rc = fts3ExprIterate2(pExpr->pLeft, piPhrase, x, pCtx); if( rc==SQLITE_OK && eType!=FTSQUERY_NOT ){ rc = fts3ExprIterate2(pExpr->pRight, piPhrase, x, pCtx); } }else{ |
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60 61 62 63 64 65 66 | ** all eligible phrase nodes. */ static int fts3ExprIterate( Fts3Expr *pExpr, /* Expression to iterate phrases of */ int (*x)(Fts3Expr*,int,void*), /* Callback function to invoke for phrases */ void *pCtx /* Second argument to pass to callback */ ){ | | > > | > > > > > | < > | < < | > > | 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 | ** all eligible phrase nodes. */ static int fts3ExprIterate( Fts3Expr *pExpr, /* Expression to iterate phrases of */ int (*x)(Fts3Expr*,int,void*), /* Callback function to invoke for phrases */ void *pCtx /* Second argument to pass to callback */ ){ int iPhrase = 0; /* Variable used as the phrase counter */ return fts3ExprIterate2(pExpr, &iPhrase, x, pCtx); } /* ** The argument to this function is always a phrase node. Its doclist ** (Fts3Expr.aDoclist[]) and the doclists associated with all phrase nodes ** to the left of this one in the query tree have already been loaded. ** ** If this phrase node is part of a series of phrase nodes joined by ** NEAR operators (and is not the left-most of said series), then elements are ** removed from the phrases doclist consistent with the NEAR restriction. If ** required, elements may be removed from the doclists of phrases to the ** left of this one that are part of the same series of NEAR operator ** connected phrases. ** ** If an OOM error occurs, SQLITE_NOMEM is returned. Otherwise, SQLITE_OK. */ static int fts3ExprNearTrim(Fts3Expr *pExpr){ int rc = SQLITE_OK; Fts3Expr *pParent = pExpr->pParent; assert( pExpr->eType==FTSQUERY_PHRASE ); while( rc==SQLITE_OK && pExpr->aDoclist && pParent |
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102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 | pExpr = pLeft; pParent = pExpr->pParent; } return rc; } static int fts3ExprLoadDoclistsCb1(Fts3Expr *pExpr, int iPhrase, void *ctx){ int rc = SQLITE_OK; LoadDoclistCtx *p = (LoadDoclistCtx *)ctx; p->nPhrase++; p->nToken += pExpr->pPhrase->nToken; if( pExpr->isLoaded==0 ){ rc = sqlite3Fts3ExprLoadDoclist(p->pTab, pExpr); pExpr->isLoaded = 1; if( rc==SQLITE_OK ){ rc = fts3ExprNearTrim(pExpr); } } return rc; } static int fts3ExprLoadDoclistsCb2(Fts3Expr *pExpr, int iPhrase, void *ctx){ if( pExpr->aDoclist ){ pExpr->pCurrent = pExpr->aDoclist; pExpr->iCurrent = 0; pExpr->pCurrent += sqlite3Fts3GetVarint(pExpr->pCurrent, &pExpr->iCurrent); } return SQLITE_OK; } static int fts3ExprLoadDoclists( | > > > > > > > > > > > > > > > > > > > > | | | < < < < < < < < < < < < < < < < < < < < < < < < | 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 | pExpr = pLeft; pParent = pExpr->pParent; } return rc; } /* ** This is an fts3ExprIterate() callback used while loading the doclists ** for each phrase into Fts3Expr.aDoclist[]/nDoclist. See also ** fts3ExprLoadDoclists(). */ static int fts3ExprLoadDoclistsCb1(Fts3Expr *pExpr, int iPhrase, void *ctx){ int rc = SQLITE_OK; LoadDoclistCtx *p = (LoadDoclistCtx *)ctx; p->nPhrase++; p->nToken += pExpr->pPhrase->nToken; if( pExpr->isLoaded==0 ){ rc = sqlite3Fts3ExprLoadDoclist(p->pTab, pExpr); pExpr->isLoaded = 1; if( rc==SQLITE_OK ){ rc = fts3ExprNearTrim(pExpr); } } return rc; } /* ** This is an fts3ExprIterate() callback used while loading the doclists ** for each phrase into Fts3Expr.aDoclist[]/nDoclist. See also ** fts3ExprLoadDoclists(). */ static int fts3ExprLoadDoclistsCb2(Fts3Expr *pExpr, int iPhrase, void *ctx){ if( pExpr->aDoclist ){ pExpr->pCurrent = pExpr->aDoclist; pExpr->iCurrent = 0; pExpr->pCurrent += sqlite3Fts3GetVarint(pExpr->pCurrent, &pExpr->iCurrent); } return SQLITE_OK; } /* ** Load the doclists for each phrase in the query associated with FTS3 cursor ** pCsr. ** ** If pnPhrase is not NULL, then *pnPhrase is set to the number of matchable ** phrases in the expression (all phrases except those directly or ** indirectly descended from the right-hand-side of a NOT operator). If ** pnToken is not NULL, then it is set to the number of tokens in all ** matchable phrases of the expression. */ static int fts3ExprLoadDoclists( Fts3Cursor *pCsr, /* Fts3 cursor for current query */ int *pnPhrase, /* OUT: Number of phrases in query */ int *pnToken /* OUT: Number of tokens in query */ ){ int rc; /* Return Code */ LoadDoclistCtx sCtx = {0,0,0}; /* Context for fts3ExprIterate() */ sCtx.pTab = (Fts3Table *)pCsr->base.pVtab; rc = fts3ExprIterate(pCsr->pExpr, fts3ExprLoadDoclistsCb1, (void *)&sCtx); if( rc==SQLITE_OK ){ (void)fts3ExprIterate(pCsr->pExpr, fts3ExprLoadDoclistsCb2, 0); } if( pnPhrase ) *pnPhrase = sCtx.nPhrase; if( pnToken ) *pnToken = sCtx.nToken; return rc; } /* ** Advance the position list iterator specified by the first two ** arguments so that it points to the first element with a value greater ** than or equal to parameter iNext. */ static void fts3SnippetAdvance(char **ppIter, int *piIter, int iNext){ char *pIter = *ppIter; |
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194 195 196 197 198 199 200 | } *piIter = iIter; *ppIter = pIter; } } | > > > | | | 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 | } *piIter = iIter; *ppIter = pIter; } } /* ** Advance the snippet iterator to the next candidate snippet. */ static int fts3SnippetNextCandidate(SnippetIter *pIter){ int i; /* Loop counter */ if( pIter->iCurrent<0 ){ /* The SnippetIter object has just been initialized. The first snippet ** candidate always starts at offset 0 (even if this candidate has a ** score of 0.0). */ pIter->iCurrent = 0; /* Advance the 'head' iterator of each phrase to the first offset that ** is greater than or equal to (iNext+nSnippet). |
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236 237 238 239 240 241 242 243 | fts3SnippetAdvance(&pPhrase->pTail, &pPhrase->iTail, iStart); } } return 0; } static void fts3SnippetDetails( | > > > > | < | | | | | 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 | fts3SnippetAdvance(&pPhrase->pTail, &pPhrase->iTail, iStart); } } return 0; } /* ** Retrieve information about the current candidate snippet of snippet ** iterator pIter. */ static void fts3SnippetDetails( SnippetIter *pIter, /* Snippet iterator */ u64 mCovered, /* Bitmask of phrases already covered */ int *piToken, /* OUT: First token of proposed snippet */ int *piScore, /* OUT: "Score" for this snippet */ u64 *pmCover, /* OUT: Bitmask of phrases covered */ u64 *pmHighlight /* OUT: Bitmask of terms to highlight */ ){ int iStart = pIter->iCurrent; /* First token of snippet */ int iScore = 0; /* Score of this snippet */ int i; /* Loop counter */ u64 mCover = 0; /* Mask of phrases covered by this snippet */ u64 mHighlight = 0; /* Mask of tokens to highlight in snippet */ for(i=0; i<pIter->nPhrase; i++){ SnippetPhrase *pPhrase = &pIter->aPhrase[i]; if( pPhrase->pTail ){ char *pCsr = pPhrase->pTail; int iCsr = pPhrase->iTail; |
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279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 | if( 0==(*pCsr & 0x0FE) ) break; fts3GetDeltaPosition(&pCsr, &iCsr); } } } *piToken = iStart; *piScore = iScore; *pmCover = mCover; *pmHighlight = mHighlight; } /* ** This function is an fts3ExprIterate() callback used by fts3BestSnippet(). | > | | | 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 | if( 0==(*pCsr & 0x0FE) ) break; fts3GetDeltaPosition(&pCsr, &iCsr); } } } /* Set the output variables before returning. */ *piToken = iStart; *piScore = iScore; *pmCover = mCover; *pmHighlight = mHighlight; } /* ** This function is an fts3ExprIterate() callback used by fts3BestSnippet(). ** Each invocation populates an element of the SnippetIter.aPhrase[] array. */ static int fts3SnippetFindPositions(Fts3Expr *pExpr, int iPhrase, void *ctx){ SnippetIter *p = (SnippetIter *)ctx; SnippetPhrase *pPhrase = &p->aPhrase[iPhrase]; char *pCsr; pPhrase->nToken = pExpr->pPhrase->nToken; pCsr = sqlite3Fts3FindPositions(pExpr, p->pCsr->iPrevId, p->iCol); if( pCsr ){ |
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312 313 314 315 316 317 318 | }else{ assert( pPhrase->pList==0 && pPhrase->pHead==0 && pPhrase->pTail==0 ); } return SQLITE_OK; } | < | | > | | | | > > | < | > > > > | | | | | | | | | | | | | | > | > > > | | < | < > | | | | < | | | | > > > > > > > > > > > > > > > > > > > > > > > > > | | | | | | | | | | > > > | > > > > | | | > > | > | 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 | }else{ assert( pPhrase->pList==0 && pPhrase->pHead==0 && pPhrase->pTail==0 ); } return SQLITE_OK; } /* ** Select the fragment of text consisting of nFragment contiguous tokens ** from column iCol that represent the "best" snippet. The best snippet ** is the snippet with the highest score, where scores are calculated ** by adding: ** ** (a) +1 point for each occurence of a matchable phrase in the snippet. ** ** (b) +1000 points for the first occurence of each matchable phrase in ** the snippet for which the corresponding mCovered bit is not set. ** ** The selected snippet parameters are stored in structure *pFragment before ** returning. The score of the selected snippet is stored in *piScore ** before returning. */ static int fts3BestSnippet( int nSnippet, /* Desired snippet length */ Fts3Cursor *pCsr, /* Cursor to create snippet for */ int iCol, /* Index of column to create snippet from */ u64 mCovered, /* Mask of phrases already covered */ u64 *pmSeen, /* IN/OUT: Mask of phrases seen */ SnippetFragment *pFragment, /* OUT: Best snippet found */ int *piScore /* OUT: Score of snippet pFragment */ ){ int rc; /* Return Code */ int nList; /* Number of phrases in expression */ SnippetIter sIter; /* Iterates through snippet candidates */ int nByte; /* Number of bytes of space to allocate */ int iBestScore = -1; /* Best snippet score found so far */ int i; /* Loop counter */ memset(&sIter, 0, sizeof(sIter)); /* Iterate through the phrases in the expression to count them. The same ** callback makes sure the doclists are loaded for each phrase. */ rc = fts3ExprLoadDoclists(pCsr, &nList, 0); if( rc!=SQLITE_OK ){ return rc; } /* Now that it is known how many phrases there are, allocate and zero ** the required space using malloc(). */ nByte = sizeof(SnippetPhrase) * nList; sIter.aPhrase = (SnippetPhrase *)sqlite3_malloc(nByte); if( !sIter.aPhrase ){ return SQLITE_NOMEM; } memset(sIter.aPhrase, 0, nByte); /* Initialize the contents of the SnippetIter object. Then iterate through ** the set of phrases in the expression to populate the aPhrase[] array. */ sIter.pCsr = pCsr; sIter.iCol = iCol; sIter.nSnippet = nSnippet; sIter.nPhrase = nList; sIter.iCurrent = -1; (void)fts3ExprIterate(pCsr->pExpr, fts3SnippetFindPositions, (void *)&sIter); /* Set the *pmSeen output variable. */ for(i=0; i<nList; i++){ if( sIter.aPhrase[i].pHead ){ *pmSeen |= (u64)1 << i; } } /* Loop through all candidate snippets. Store the best snippet in ** *pFragment. Store its associated 'score' in iBestScore. */ pFragment->iCol = iCol; while( !fts3SnippetNextCandidate(&sIter) ){ int iPos; int iScore; u64 mCover; u64 mHighlight; fts3SnippetDetails(&sIter, mCovered, &iPos, &iScore, &mCover, &mHighlight); assert( iScore>=0 ); if( iScore>iBestScore ){ pFragment->iPos = iPos; pFragment->hlmask = mHighlight; pFragment->covered = mCover; iBestScore = iScore; } } sqlite3_free(sIter.aPhrase); *piScore = iBestScore; return SQLITE_OK; } /* ** Append a string to the string-buffer passed as the first argument. ** ** If nAppend is negative, then the length of the string zAppend is ** determined using strlen(). */ static int fts3StringAppend( StrBuffer *pStr, /* Buffer to append to */ const char *zAppend, /* Pointer to data to append to buffer */ int nAppend /* Size of zAppend in bytes (or -1) */ ){ if( nAppend<0 ){ nAppend = strlen(zAppend); } /* If there is insufficient space allocated at StrBuffer.z, use realloc() ** to grow the buffer until so that it is big enough to accomadate the ** appended data. */ if( pStr->n+nAppend+1>=pStr->nAlloc ){ int nAlloc = pStr->nAlloc+nAppend+100; char *zNew = sqlite3_realloc(pStr->z, nAlloc); if( !zNew ){ return SQLITE_NOMEM; } pStr->z = zNew; pStr->nAlloc = nAlloc; } /* Append the data to the string buffer. */ memcpy(&pStr->z[pStr->n], zAppend, nAppend); pStr->n += nAppend; pStr->z[pStr->n] = '\0'; return SQLITE_OK; } /* ** The fts3BestSnippet() function often selects snippets that end with a ** query term. That is, the final term of the snippet is always a term ** that requires highlighting. For example, if 'X' is a highlighted term ** and '.' is a non-highlighted term, BestSnippet() may select: ** ** ........X.....X ** ** This function "shifts" the beginning of the snippet forward in the ** document so that there are approximately the same number of ** non-highlighted terms to the right of the final highlighted term as there ** are to the left of the first highlighted term. For example, to this: ** ** ....X.....X.... ** ** This is done as part of extracting the snippet text, not when selecting ** the snippet. Snippet selection is done based on doclists only, so there ** is no way for fts3BestSnippet() to know whether or not the document ** actually contains terms that follow the final highlighted term. */ int fts3SnippetShift( Fts3Table *pTab, /* FTS3 table snippet comes from */ int nSnippet, /* Number of tokens desired for snippet */ const char *zDoc, /* Document text to extract snippet from */ int nDoc, /* Size of buffer zDoc in bytes */ int *piPos, /* IN/OUT: First token of snippet */ u64 *pHlmask /* IN/OUT: Mask of tokens to highlight */ ){ u64 hlmask = *pHlmask; /* Local copy of initial highlight-mask */ if( hlmask ){ int nLeft; /* Tokens to the left of first highlight */ int nRight; /* Tokens to the right of last highlight */ int nDesired; /* Ideal number of tokens to shift forward */ for(nLeft=0; !(hlmask & ((u64)1 << nLeft)); nLeft++); for(nRight=0; !(hlmask & ((u64)1 << (nSnippet-1-nRight))); nRight++); nDesired = (nLeft-nRight)/2; /* Ideally, the start of the snippet should be pushed forward in the ** document nDesired tokens. This block checks if there are actually ** nDesired tokens to the right of the snippet. If so, *piPos and ** *pHlMask are updated to shift the snippet nDesired tokens to the ** right. Otherwise, the snippet is shifted by the number of tokens ** available. */ if( nDesired>0 ){ int nShift; /* Number of tokens to shift snippet by */ int iCurrent = 0; /* Token counter */ int rc; /* Return Code */ sqlite3_tokenizer_module *pMod; sqlite3_tokenizer_cursor *pC; pMod = (sqlite3_tokenizer_module *)pTab->pTokenizer->pModule; /* Open a cursor on zDoc/nDoc. Check if there are (nSnippet+nDesired) ** or more tokens in zDoc/nDoc. */ rc = pMod->xOpen(pTab->pTokenizer, zDoc, nDoc, &pC); if( rc!=SQLITE_OK ){ return rc; } pC->pTokenizer = pTab->pTokenizer; while( rc==SQLITE_OK && iCurrent<(nSnippet+nDesired) ){ const char *ZDUMMY; int DUMMY1, DUMMY2, DUMMY3; |
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480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 | *pHlmask = hlmask >> nShift; } } } return SQLITE_OK; } static int fts3SnippetText( Fts3Cursor *pCsr, /* FTS3 Cursor */ SnippetFragment *pFragment, /* Snippet to extract */ int iFragment, /* Fragment number */ int isLast, /* True for final fragment in snippet */ int nSnippet, /* Number of tokens in extracted snippet */ const char *zOpen, /* String inserted before highlighted term */ const char *zClose, /* String inserted after highlighted term */ | > > > > | | | | | | | | | | | | | 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 | *pHlmask = hlmask >> nShift; } } } return SQLITE_OK; } /* ** Extract the snippet text for fragment pFragment from cursor pCsr and ** append it to string buffer pOut. */ static int fts3SnippetText( Fts3Cursor *pCsr, /* FTS3 Cursor */ SnippetFragment *pFragment, /* Snippet to extract */ int iFragment, /* Fragment number */ int isLast, /* True for final fragment in snippet */ int nSnippet, /* Number of tokens in extracted snippet */ const char *zOpen, /* String inserted before highlighted term */ const char *zClose, /* String inserted after highlighted term */ const char *zEllipsis, /* String inserted between snippets */ StrBuffer *pOut /* Write output here */ ){ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab; int rc; /* Return code */ const char *zDoc; /* Document text to extract snippet from */ int nDoc; /* Size of zDoc in bytes */ int iCurrent = 0; /* Current token number of document */ int iEnd = 0; /* Byte offset of end of current token */ int isShiftDone = 0; /* True after snippet is shifted */ int iPos = pFragment->iPos; /* First token of snippet */ u64 hlmask = pFragment->hlmask; /* Highlight-mask for snippet */ int iCol = pFragment->iCol+1; /* Query column to extract text from */ sqlite3_tokenizer_module *pMod; /* Tokenizer module methods object */ sqlite3_tokenizer_cursor *pC; /* Tokenizer cursor open on zDoc/nDoc */ const char *ZDUMMY; /* Dummy argument used with tokenizer */ int DUMMY1; /* Dummy argument used with tokenizer */ zDoc = (const char *)sqlite3_column_text(pCsr->pStmt, iCol); if( zDoc==0 ){ if( sqlite3_column_type(pCsr->pStmt, iCol)!=SQLITE_NULL ){ return SQLITE_NOMEM; } return SQLITE_OK; } nDoc = sqlite3_column_bytes(pCsr->pStmt, iCol); /* Open a token cursor on the document. */ pMod = (sqlite3_tokenizer_module *)pTab->pTokenizer->pModule; rc = pMod->xOpen(pTab->pTokenizer, zDoc, nDoc, &pC); if( rc!=SQLITE_OK ){ return rc; } pC->pTokenizer = pTab->pTokenizer; while( rc==SQLITE_OK ){ int iBegin; /* Offset in zDoc of start of token */ int iFin; /* Offset in zDoc of end of token */ int isHighlight; /* True for highlighted terms */ rc = pMod->xNext(pC, &ZDUMMY, &DUMMY1, &iBegin, &iFin, &iCurrent); if( rc!=SQLITE_OK ){ if( rc==SQLITE_DONE ){ /* Special case - the last token of the snippet is also the last token ** of the column. Append any punctuation that occurred between the end ** of the previous token and the end of the document to the output. |
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580 581 582 583 584 585 586 | pMod->xClose(pC); return rc; } /* | | | | < < | < | < > | < | < < < < < | < < < < < < < < < < | < < < | > | > > > > | > | | | | < > > > > > | < > | > | > | > | | | > > > > > > > > > | | | < < | < | < | | | > > | | | | < < < < | < | > > > | 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 | pMod->xClose(pC); return rc; } /* ** This function is used to count the entries in a column-list (a ** delta-encoded list of term offsets within a single column of a single ** row). When this function is called, *ppCollist should point to the ** beginning of the first varint in the column-list (the varint that ** contains the position of the first matching term in the column data). ** Before returning, *ppCollist is set to point to the first byte after ** the last varint in the column-list (either the 0x00 signifying the end ** of the position-list, or the 0x01 that precedes the column number of ** the next column in the position-list). ** ** The number of elements in the column-list is returned. */ static int fts3ColumnlistCount(char **ppCollist){ char *pEnd = *ppCollist; char c = 0; int nEntry = 0; /* A column-list is terminated by either a 0x01 or 0x00. */ while( 0xFE & (*pEnd | c) ){ c = *pEnd++ & 0x80; if( !c ) nEntry++; } *ppCollist = pEnd; return nEntry; } static void fts3LoadColumnlistCounts(char **pp, u32 *aOut, int isGlobal){ char *pCsr = *pp; while( *pCsr ){ int nHit; sqlite3_int64 iCol = 0; if( *pCsr==0x01 ){ pCsr++; pCsr += sqlite3Fts3GetVarint(pCsr, &iCol); } nHit = fts3ColumnlistCount(&pCsr); if( isGlobal ){ if( nHit ) aOut[iCol*3+1]++; } aOut[iCol*3] += nHit; } pCsr++; *pp = pCsr; } /* ** fts3ExprIterate() callback used to collect the "global" matchinfo stats ** for a single query. The "global" stats are those elements of the matchinfo ** array that are constant for all rows returned by the current query. */ static int fts3ExprGlobalMatchinfoCb( Fts3Expr *pExpr, /* Phrase expression node */ int iPhrase, /* Phrase number (numbered from zero) */ void *pCtx /* Pointer to MatchInfo structure */ ){ MatchInfo *p = (MatchInfo *)pCtx; char *pCsr; char *pEnd; const int iStart = 2 + (iPhrase * p->nCol * 3) + 1; assert( pExpr->isLoaded ); /* Fill in the global hit count matrix row for this phrase. */ pCsr = pExpr->aDoclist; pEnd = &pExpr->aDoclist[pExpr->nDoclist]; while( pCsr<pEnd ){ while( *pCsr++ & 0x80 ); /* Skip past docid. */ fts3LoadColumnlistCounts(&pCsr, &p->aMatchinfo[iStart], 1); } return SQLITE_OK; } /* ** fts3ExprIterate() callback used to collect the "local" matchinfo stats ** for a single query. The "local" stats are those elements of the matchinfo ** array that are different for each row returned by the query. */ static int fts3ExprLocalMatchinfoCb( Fts3Expr *pExpr, /* Phrase expression node */ int iPhrase, /* Phrase number */ void *pCtx /* Pointer to MatchInfo structure */ ){ MatchInfo *p = (MatchInfo *)pCtx; if( pExpr->aDoclist ){ char *pCsr; int iStart = 2 + (iPhrase * p->nCol * 3); int i; for(i=0; i<p->nCol; i++) p->aMatchinfo[iStart+i*3] = 0; pCsr = sqlite3Fts3FindPositions(pExpr, p->pCursor->iPrevId, -1); if( pCsr ){ fts3LoadColumnlistCounts(&pCsr, &p->aMatchinfo[iStart], 0); } } return SQLITE_OK; } /* ** Populate pCsr->aMatchinfo[] with data for the current row. The ** 'matchinfo' data is an array of 32-bit unsigned integers (C type u32). */ static int fts3GetMatchinfo(Fts3Cursor *pCsr){ MatchInfo sInfo; Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab; sInfo.pCursor = pCsr; sInfo.nCol = pTab->nColumn; if( pCsr->aMatchinfo==0 ){ /* If Fts3Cursor.aMatchinfo[] is NULL, then this is the first time the ** matchinfo function has been called for this query. In this case ** allocate the array used to accumulate the matchinfo data and ** initialize those elements that are constant for every row. */ int rc; /* Return Code */ int nPhrase; /* Number of phrases */ int nMatchinfo; /* Number of u32 elements in match-info */ /* Load doclists for each phrase in the query. */ rc = fts3ExprLoadDoclists(pCsr, &nPhrase, 0); if( rc!=SQLITE_OK ){ return rc; } nMatchinfo = 2 + 3*sInfo.nCol*nPhrase; sInfo.aMatchinfo = (u32 *)sqlite3_malloc(sizeof(u32)*nMatchinfo); if( !sInfo.aMatchinfo ){ return SQLITE_NOMEM; } memset(sInfo.aMatchinfo, 0, sizeof(u32)*nMatchinfo); /* First element of match-info is the number of phrases in the query */ sInfo.aMatchinfo[0] = nPhrase; sInfo.aMatchinfo[1] = sInfo.nCol; (void)fts3ExprIterate(pCsr->pExpr, fts3ExprGlobalMatchinfoCb,(void*)&sInfo); pCsr->aMatchinfo = sInfo.aMatchinfo; } sInfo.aMatchinfo = pCsr->aMatchinfo; if( pCsr->isMatchinfoOk ){ (void)fts3ExprIterate(pCsr->pExpr, fts3ExprLocalMatchinfoCb, (void*)&sInfo); pCsr->isMatchinfoOk = 0; } return SQLITE_OK; } /* ** Implementation of snippet() function. */ void sqlite3Fts3Snippet( sqlite3_context *pCtx, /* SQLite function call context */ Fts3Cursor *pCsr, /* Cursor object */ const char *zStart, /* Snippet start text - "<b>" */ const char *zEnd, /* Snippet end text - "</b>" */ const char *zEllipsis, /* Snippet ellipsis text - "<b>...</b>" */ int iCol, /* Extract snippet from this column */ |
︙ | ︙ | |||
831 832 833 834 835 836 837 838 839 840 | }else{ sqlite3_result_text(pCtx, res.z, -1, sqlite3_free); } } typedef struct TermOffset TermOffset; struct TermOffset { char *pList; /* Position-list */ int iPos; /* Position just read from pList */ | > > | < | 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 | }else{ sqlite3_result_text(pCtx, res.z, -1, sqlite3_free); } } typedef struct TermOffset TermOffset; typedef struct TermOffsetCtx TermOffsetCtx; struct TermOffset { char *pList; /* Position-list */ int iPos; /* Position just read from pList */ int iOff; /* Offset of this term from read positions */ }; struct TermOffsetCtx { int iCol; /* Column of table to populate aTerm for */ int iTerm; sqlite3_int64 iDocid; TermOffset *aTerm; }; |
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881 882 883 884 885 886 887 | */ void sqlite3Fts3Offsets( sqlite3_context *pCtx, /* SQLite function call context */ Fts3Cursor *pCsr /* Cursor object */ ){ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab; sqlite3_tokenizer_module const *pMod = pTab->pTokenizer->pModule; | | | < > < < > > > | 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 | */ void sqlite3Fts3Offsets( sqlite3_context *pCtx, /* SQLite function call context */ Fts3Cursor *pCsr /* Cursor object */ ){ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab; sqlite3_tokenizer_module const *pMod = pTab->pTokenizer->pModule; const char *ZDUMMY; /* Dummy argument used with xNext() */ int NDUMMY; /* Dummy argument used with xNext() */ int rc; /* Return Code */ int nToken; /* Number of tokens in query */ int iCol; /* Column currently being processed */ StrBuffer res = {0, 0, 0}; /* Result string */ TermOffsetCtx sCtx; /* Context for fts3ExprTermOffsetInit() */ memset(&sCtx, 0, sizeof(sCtx)); assert( pCsr->isRequireSeek==0 ); /* Count the number of terms in the query */ rc = fts3ExprLoadDoclists(pCsr, 0, &nToken); if( rc!=SQLITE_OK ) goto offsets_out; /* Allocate the array of TermOffset iterators. */ sCtx.aTerm = (TermOffset *)sqlite3_malloc(sizeof(TermOffset)*nToken); if( 0==sCtx.aTerm ){ rc = SQLITE_NOMEM; goto offsets_out; } sCtx.iDocid = pCsr->iPrevId; /* Loop through the table columns, appending offset information to ** string-buffer res for each column. */ for(iCol=0; iCol<pTab->nColumn; iCol++){ sqlite3_tokenizer_cursor *pC; /* Tokenizer cursor */ int iStart; int iEnd; int iCurrent; const char *zDoc; int nDoc; |
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997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 | sqlite3_free(res.z); }else{ sqlite3_result_text(pCtx, res.z, res.n-1, sqlite3_free); } return; } void sqlite3Fts3Matchinfo(sqlite3_context *pContext, Fts3Cursor *pCsr){ int rc = fts3GetMatchinfo(pCsr); if( rc!=SQLITE_OK ){ sqlite3_result_error_code(pContext, rc); }else{ | > > > | | 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 | sqlite3_free(res.z); }else{ sqlite3_result_text(pCtx, res.z, res.n-1, sqlite3_free); } return; } /* ** Implementation of matchinfo() function. */ void sqlite3Fts3Matchinfo(sqlite3_context *pContext, Fts3Cursor *pCsr){ int rc = fts3GetMatchinfo(pCsr); if( rc!=SQLITE_OK ){ sqlite3_result_error_code(pContext, rc); }else{ int n = sizeof(u32)*(2+pCsr->aMatchinfo[0]*pCsr->aMatchinfo[1]*3); sqlite3_result_blob(pContext, pCsr->aMatchinfo, n, SQLITE_TRANSIENT); } } #endif |
Changes to test/fts3query.test.
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95 96 97 98 99 100 101 | binary scan $blob $scan($::tcl_platform(byteOrder)) r return $r } db func mit mit do_test fts3query-3.3 { execsql { SELECT mit(matchinfo(foobar)) FROM foobar WHERE foobar MATCH 'the' } | | | 95 96 97 98 99 100 101 102 103 104 105 | binary scan $blob $scan($::tcl_platform(byteOrder)) r return $r } db func mit mit do_test fts3query-3.3 { execsql { SELECT mit(matchinfo(foobar)) FROM foobar WHERE foobar MATCH 'the' } } {{1 1 3 3 1}} finish_test |