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Overview
Comment:Add the "unionvtab" virtual table extension in ext/misc/unionvtab.c.
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Timelines: family | ancestors | descendants | both | union-vtab
Files: files | file ages | folders
SHA3-256:62a86aa6c0519cf1fa232169122d3d6ae8d2f66b20530fb934a82a15712bd2f0
User & Date: dan 2017-07-15 20:48:30
Context
2017-07-17
20:25
Enhance error detection and fix other issues in unionvtab code. check-in: 9c3f1b9a user: dan tags: union-vtab
09:30
Use integer handles for fts3 cursors for a small performance improvement. Closed-Leaf check-in: f4f7196b user: dan tags: union-vtab, fts3-int-cursor
2017-07-15
20:48
Add the "unionvtab" virtual table extension in ext/misc/unionvtab.c. check-in: 62a86aa6 user: dan tags: union-vtab
20:33
Fix a register allocation problem in PRAGMA integrity_check that caused the same register to be used for two different purposes on the first ATTACHed database if the schema for the ATTACHed database was noticable more complex than the schema for the first database. Fix for ticket [a4e06e75a9ab61a1]. check-in: 253945d4 user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to Makefile.in.

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  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/percentile.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/remember.c \
  $(TOP)/ext/misc/series.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/totype.c \

  $(TOP)/ext/misc/wholenumber.c

# Source code to the library files needed by the test fixture
#
TESTSRC2 = \
  $(TOP)/src/attach.c \
  $(TOP)/src/backup.c \







>







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  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/percentile.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/remember.c \
  $(TOP)/ext/misc/series.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/totype.c \
  $(TOP)/ext/misc/unionvtab.c \
  $(TOP)/ext/misc/wholenumber.c

# Source code to the library files needed by the test fixture
#
TESTSRC2 = \
  $(TOP)/src/attach.c \
  $(TOP)/src/backup.c \

Added ext/misc/unionvtab.c.





































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































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/*
** 2017 July 15
**
** 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.
**
*************************************************************************
**
*/
#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_UNIONVTAB)

#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <assert.h>
#include <string.h>

#ifndef SQLITE_OMIT_VIRTUALTABLE

typedef struct UnionCsr UnionCsr;
typedef struct UnionTab UnionTab;
typedef struct UnionSrc UnionSrc;

/*
** Each source table (row returned by the initialization query) is 
** represented by an instance of the following structure stored in the
** UnionTab.aSrc[] array.
*/
struct UnionSrc {
  char *zDb;                      /* Database containing source table */
  char *zTab;                     /* Source table name */
  sqlite3_int64 iMin;             /* Minimum rowid */
  sqlite3_int64 iMax;             /* Maximum rowid */
};

/*
** Virtual table cursor type for union vtab.
*/
struct UnionCsr {
  sqlite3_vtab_cursor base;       /* Base class - must be first */
  sqlite3_stmt *pStmt;            /* SQL statement to run */
};

/*
** Virtual table  type for union vtab.
*/
struct UnionTab {
  sqlite3_vtab base;              /* Base class - must be first */
  sqlite3 *db;                    /* Database handle */
  int nSrc;                       /* Number of elements in the aSrc[] array */
  UnionSrc *aSrc;                 /* Array of source tables, sorted by rowid */
};

/*
** If *pRc is other than SQLITE_OK when this function is called, it
** always returns NULL. Otherwise, it attempts to allocate and return
** a pointer to nByte bytes of zeroed memory. If the memory allocation
** is attempted but fails, NULL is returned and *pRc is set to 
** SQLITE_NOMEM.
*/
static void *unionMalloc(int *pRc, int nByte){
  void *pRet;
  assert( nByte>0 );
  if( *pRc==SQLITE_OK ){
    pRet = sqlite3_malloc(nByte);
    if( pRet ){
      memset(pRet, 0, nByte);
    }else{
      *pRc = SQLITE_NOMEM;
    }
  }else{
    pRet = 0;
  }
  return pRet;
}

/*
** If *pRc is other than SQLITE_OK when this function is called, it
** always returns NULL. Otherwise, it attempts to allocate and return
** a copy of the nul-terminated string passed as the second argument.
** If the allocation is attempted but fails, NULL is returned and *pRc is 
** set to SQLITE_NOMEM.
*/
static char *unionStrdup(int *pRc, const char *zIn){
  char *zRet = 0;
  if( zIn ){
    int nByte = strlen(zIn) + 1;
    zRet = unionMalloc(pRc, nByte);
    if( zRet ){
      memcpy(zRet, zIn, nByte);
    }
  }
  return zRet;
}

/*
** If the first character of the string passed as the only argument to this
** function is one of the 4 that may be used as an open quote character
** in SQL, this function assumes that the input is a well-formed quoted SQL 
** string. In this case the string is dequoted in place.
**
** If the first character of the input is not an open quote, then this
** function is a no-op.
*/
static void unionDequote(char *z){
  char q = z[0];

  /* Set stack variable q to the close-quote character */
  if( q=='[' || q=='\'' || q=='"' || q=='`' ){
    int iIn = 1;
    int iOut = 0;
    if( q=='[' ) q = ']';  
    while( z[iIn] ){
      if( z[iIn]==q ){
        if( z[iIn+1]!=q ){
          /* Character iIn was the close quote. */
          iIn++;
          break;
        }else{
          /* Character iIn and iIn+1 form an escaped quote character. Skip
          ** the input cursor past both and copy a single quote character 
          ** to the output buffer. */
          iIn += 2;
          z[iOut++] = q;
        }
      }else{
        z[iOut++] = z[iIn++];
      }
    }
    z[iOut] = '\0';
  }
}

static sqlite3_stmt *unionPrepare(
  int *pRc, 
  sqlite3 *db, 
  const char *zSql, 
  char **pzErr
){
  sqlite3_stmt *pRet = 0;
  if( *pRc==SQLITE_OK ){
    int rc = sqlite3_prepare_v2(db, zSql, -1, &pRet, 0);
    if( rc!=SQLITE_OK ){
      *pzErr = sqlite3_mprintf("sql error: %s", sqlite3_errmsg(db));
      *pRc = rc;
    }
  }
  return pRet;
}

static void unionReset(int *pRc, sqlite3_stmt *pStmt, char **pzErr){
  int rc = sqlite3_reset(pStmt);
  if( *pRc==SQLITE_OK ){
    *pRc = rc;
    if( rc && pzErr ){
      *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(sqlite3_db_handle(pStmt)));
    }
  }
}

static void unionFinalize(int *pRc, sqlite3_stmt *pStmt){
  int rc = sqlite3_finalize(pStmt);
  if( *pRc==SQLITE_OK ) *pRc = rc;
}

/*
** xDisconnect method.
*/
static int unionDisconnect(sqlite3_vtab *pVtab){
  if( pVtab ){
    UnionTab *pTab = (UnionTab*)pVtab;
    int i;
    for(i=0; i<pTab->nSrc; i++){
      sqlite3_free(pTab->aSrc[i].zDb);
      sqlite3_free(pTab->aSrc[i].zTab);
    }
    sqlite3_free(pTab->aSrc);
    sqlite3_free(pTab);
  }
  return SQLITE_OK;
}

static char *unionSourceToStr(
  int *pRc,
  UnionSrc *pSrc, 
  sqlite3_stmt *pStmt,
  char **pzErr
){
  char *zRet = 0;
  if( *pRc==SQLITE_OK ){
    sqlite3_bind_text(pStmt, 1, pSrc->zTab, -1, SQLITE_STATIC);
    sqlite3_bind_text(pStmt, 2, pSrc->zDb, -1, SQLITE_STATIC);
    if( SQLITE_ROW==sqlite3_step(pStmt) ){
      zRet = unionStrdup(pRc, (const char*)sqlite3_column_text(pStmt, 0));
    }
    unionReset(pRc, pStmt, pzErr);
    if( *pRc==SQLITE_OK && zRet==0 ){
      *pRc = SQLITE_ERROR;
      *pzErr = sqlite3_mprintf("no such table: %s%s%s",
          (pSrc->zDb ? pSrc->zDb : ""),
          (pSrc->zDb ? "." : ""),
          pSrc->zTab
      );
    }
  }
  return zRet;
}

static int unionSourceCheck(UnionTab *pTab, char **pzErr){
  const char *zSql = 
      "SELECT group_concat(quote(name) || '.' || quote(type)) "
      "FROM pragma_table_info(?, ?)";
  int rc = SQLITE_OK;

  if( pTab->nSrc==0 ){
    *pzErr = sqlite3_mprintf("no source tables configured");
    rc = SQLITE_ERROR;
  }else{
    sqlite3_stmt *pStmt = 0;
    char *z0 = 0;
    int i;

    pStmt = unionPrepare(&rc, pTab->db, zSql, pzErr);
    if( rc==SQLITE_OK ){
      z0 = unionSourceToStr(&rc, &pTab->aSrc[0], pStmt, pzErr);
    }
    for(i=1; i<pTab->nSrc; i++){
      char *z = unionSourceToStr(&rc, &pTab->aSrc[i], pStmt, pzErr);
      if( rc==SQLITE_OK && sqlite3_stricmp(z, z0) ){
        *pzErr = sqlite3_mprintf("source table schema mismatch");
        rc = SQLITE_ERROR;
      }
      sqlite3_free(z);
    }

    unionFinalize(&rc, pStmt);
    sqlite3_free(z0);
  }
  return rc;
}

/* 
** xConnect/xCreate method.
**
** The argv[] array contains the following:
**
**   argv[0]   -> module name  ("unionvtab")
**   argv[1]   -> database name
**   argv[2]   -> table name
**   argv[3]   -> SQL statement
*/
static int unionConnect(
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  UnionTab *pTab = 0;
  int rc = SQLITE_OK;

  if( sqlite3_stricmp("temp", argv[1]) ){
    /* unionvtab tables may only be created in the temp schema */
    *pzErr = sqlite3_mprintf("unionvtab tables must be created in TEMP schema");
    rc = SQLITE_ERROR;
  }else if( argc!=4 ){
    *pzErr = sqlite3_mprintf("wrong number of arguments for unionvtab");
    rc = SQLITE_ERROR;
  }else{
    int nAlloc = 0;               /* Allocated size of pTab->aSrc[] */
    sqlite3_stmt *pStmt = 0;      /* Argument statement */
    char *zSql1 = unionStrdup(&rc, argv[3]);
    char *zSql2 = 0;

    if( zSql1 ){
      unionDequote(zSql1);
      zSql2 = sqlite3_mprintf("SELECT * FROM (%s) ORDER BY 3", zSql1);
      sqlite3_free(zSql1);
      zSql1 = 0;
    }
    if( zSql2==0 ){
      rc = SQLITE_NOMEM;
    }
    pTab = unionMalloc(&rc, sizeof(UnionTab));
    pStmt = unionPrepare(&rc, db, zSql2, pzErr);

    while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){
      const char *zDb = (const char*)sqlite3_column_text(pStmt, 0);
      const char *zTab = (const char*)sqlite3_column_text(pStmt, 1);
      sqlite3_int64 iMin = sqlite3_column_int64(pStmt, 2);
      sqlite3_int64 iMax = sqlite3_column_int64(pStmt, 3);
      UnionSrc *pSrc;

      if( nAlloc<=pTab->nSrc ){
        int nNew = nAlloc ? nAlloc*2 : 8;
        UnionSrc *aNew = (UnionSrc*)sqlite3_realloc(
            pTab->aSrc, nNew*sizeof(UnionSrc)
        );
        if( aNew==0 ){
          rc = SQLITE_NOMEM;
          break;
        }else{
          memset(&aNew[pTab->nSrc], 0, (nNew-pTab->nSrc)*sizeof(UnionSrc));
          pTab->aSrc = aNew;
          nAlloc = nNew;
        }
      }

      if( iMax<iMin || (pTab->nSrc>0 && iMin<=pTab->aSrc[pTab->nSrc-1].iMax) ){
        *pzErr = sqlite3_mprintf("rowid range mismatch error");
        rc = SQLITE_ERROR;
      }

      pSrc = &pTab->aSrc[pTab->nSrc++];
      pSrc->zDb = unionStrdup(&rc, zDb);
      pSrc->zTab = unionStrdup(&rc, zTab);
      pSrc->iMin = iMin;
      pSrc->iMax = iMax;
    }
    unionFinalize(&rc, pStmt);
    pStmt = 0;
    sqlite3_free(zSql1);
    sqlite3_free(zSql2);
    zSql1 = 0;
    zSql2 = 0;

    /* Verify that all source tables exist and have compatible schemas. */
    if( rc==SQLITE_OK ){
      pTab->db = db;
      rc = unionSourceCheck(pTab, pzErr);
    }

    /* Compose a CREATE TABLE statement and pass it to declare_vtab() */
    if( rc==SQLITE_OK ){
      zSql1 = sqlite3_mprintf("SELECT "
          "'CREATE TABLE xyz('"
          "    || group_concat(quote(name) || ' ' || type, ', ')"
          "    || ')'"
          "FROM pragma_table_info(%Q, ?)", 
          pTab->aSrc[0].zTab
      );
      if( zSql1==0 ) rc = SQLITE_NOMEM;
    }
    pStmt = unionPrepare(&rc, db, zSql1, pzErr);
    if( rc==SQLITE_OK ){
      sqlite3_bind_text(pStmt, 1, pTab->aSrc[0].zDb, -1, SQLITE_STATIC);
      if( SQLITE_ROW==sqlite3_step(pStmt) ){
        const char *zDecl = (const char*)sqlite3_column_text(pStmt, 0);
        rc = sqlite3_declare_vtab(db, zDecl);
      }
    }

    unionFinalize(&rc, pStmt);
    sqlite3_free(zSql1);
  }

  if( rc!=SQLITE_OK ){
    unionDisconnect((sqlite3_vtab*)pTab);
    pTab = 0;
  }

  *ppVtab = (sqlite3_vtab*)pTab;
  return rc;
}


/*
** xOpen
*/
static int unionOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
  UnionCsr *pCsr;
  int rc = SQLITE_OK;
  pCsr = (UnionCsr*)unionMalloc(&rc, sizeof(UnionCsr));
  *ppCursor = &pCsr->base;
  return rc;
}

/*
** xClose
*/
static int unionClose(sqlite3_vtab_cursor *cur){
  UnionCsr *pCsr = (UnionCsr*)cur;
  sqlite3_finalize(pCsr->pStmt);
  sqlite3_free(pCsr);
  return SQLITE_OK;
}


/*
** xNext
*/
static int unionNext(sqlite3_vtab_cursor *cur){
  UnionCsr *pCsr = (UnionCsr*)cur;
  int rc;
  assert( pCsr->pStmt );
  if( sqlite3_step(pCsr->pStmt)!=SQLITE_ROW ){
    rc = sqlite3_finalize(pCsr->pStmt);
    pCsr->pStmt = 0;
  }else{
    rc = SQLITE_OK;
  }
  return rc;
}

/*
** xColumn
*/
static int unionColumn(
  sqlite3_vtab_cursor *cur,
  sqlite3_context *ctx,
  int i
){
  UnionCsr *pCsr = (UnionCsr*)cur;
  sqlite3_result_value(ctx, sqlite3_column_value(pCsr->pStmt, i+1));
  return SQLITE_OK;
}

/*
** xRowid
*/
static int unionRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
  UnionCsr *pCsr = (UnionCsr*)cur;
  *pRowid = sqlite3_column_int64(pCsr->pStmt, 0);
  return SQLITE_OK;
}

/*
** xEof
*/
static int unionEof(sqlite3_vtab_cursor *cur){
  UnionCsr *pCsr = (UnionCsr*)cur;
  return pCsr->pStmt==0;
}

/*
** xFilter
*/
static int unionFilter(
  sqlite3_vtab_cursor *pVtabCursor, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  UnionTab *pTab = (UnionTab*)(pVtabCursor->pVtab);
  UnionCsr *pCsr = (UnionCsr*)pVtabCursor;
  int rc = SQLITE_OK;
  int i;
  char *zSql = 0;

  int bMinValid = 0;
  int bMaxValid = 0;
  sqlite3_int64 iMin;
  sqlite3_int64 iMax;

  if( idxNum==SQLITE_INDEX_CONSTRAINT_EQ ){
    assert( argc==1 );
    iMin = iMax = sqlite3_value_int64(argv[0]);
    bMinValid = bMaxValid = 1;
  }else{
    if( idxNum & SQLITE_INDEX_CONSTRAINT_LE ){
      assert( argc>=1 );
      iMax = sqlite3_value_int64(argv[0]);
      bMaxValid = 1;
    }
    if( idxNum & SQLITE_INDEX_CONSTRAINT_GE ){
      assert( argc>=1 );
      iMin = sqlite3_value_int64(argv[argc-1]);
      bMinValid = 1;
    }
  }


  sqlite3_finalize(pCsr->pStmt);
  pCsr->pStmt = 0;

  for(i=0; i<pTab->nSrc; i++){
    UnionSrc *pSrc = &pTab->aSrc[i];
    if( (bMinValid && iMin>pSrc->iMax) || (bMaxValid && iMax<pSrc->iMin) ){
      continue;
    }

    zSql = sqlite3_mprintf("%z%sSELECT rowid, * FROM %s%q%s%Q"
        , zSql
        , (zSql ? " UNION ALL " : "")
        , (pSrc->zDb ? "'" : "")
        , (pSrc->zDb ? pSrc->zDb : "")
        , (pSrc->zDb ? "'." : "")
        , pSrc->zTab
    );
    if( zSql==0 ){
      rc = SQLITE_NOMEM;
      break;
    }

    if( zSql ){
      if( bMinValid && bMaxValid && iMin==iMax ){
        zSql = sqlite3_mprintf("%z WHERE rowid=%lld", zSql, iMin);
      }else{
        const char *zWhere = "WHERE";
        if( bMinValid && iMin>pSrc->iMin ){
          zSql = sqlite3_mprintf("%z WHERE rowid>=%lld", zSql, iMin);
          zWhere = "AND";
        }
        if( bMaxValid && iMax<pSrc->iMax ){
          zSql = sqlite3_mprintf("%z %s rowid<=%lld", zSql, zWhere, iMax);
        }
      }
    }
  }

  if( rc==SQLITE_OK ){
    pCsr->pStmt = unionPrepare(&rc, pTab->db, zSql, &pTab->base.zErrMsg);
  }
  sqlite3_free(zSql);

  if( rc!=SQLITE_OK ) return rc;
  return unionNext(pVtabCursor);
}

/*
** xBestIndex.
*/
static int unionBestIndex(
  sqlite3_vtab *tab,
  sqlite3_index_info *pIdxInfo
){
  int iEq = -1;
  int iLt = -1;
  int iGt = -1;
  int i;

  for(i=0; i<pIdxInfo->nConstraint; i++){
    struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[i];
    if( p->usable && p->iColumn<0 ){
      switch( p->op ){
        case SQLITE_INDEX_CONSTRAINT_EQ:
          if( iEq<0 ) iEq = i;
          break;
        case SQLITE_INDEX_CONSTRAINT_LE:
        case SQLITE_INDEX_CONSTRAINT_LT:
          if( iLt<0 ) iLt = i;
          break;
        case SQLITE_INDEX_CONSTRAINT_GE:
        case SQLITE_INDEX_CONSTRAINT_GT:
          if( iGt<0 ) iGt = i;
          break;
      }
    }
  }

  if( iEq>=0 ){
    pIdxInfo->estimatedRows = 1;
    pIdxInfo->idxFlags = SQLITE_INDEX_SCAN_UNIQUE;
    pIdxInfo->estimatedCost = 3.0;
    pIdxInfo->idxNum = SQLITE_INDEX_CONSTRAINT_EQ;
    pIdxInfo->aConstraintUsage[iEq].argvIndex = 1;
  }else{
    int iCons = 1;
    int idxNum = 0;
    sqlite3_int64 nRow = 1000000;
    if( iLt>=0 ){
      nRow = nRow / 2;
      pIdxInfo->aConstraintUsage[iLt].argvIndex = iCons++;
      idxNum |= SQLITE_INDEX_CONSTRAINT_LE;
    }
    if( iGt>=0 ){
      nRow = nRow / 2;
      pIdxInfo->aConstraintUsage[iGt].argvIndex = iCons++;
      idxNum |= SQLITE_INDEX_CONSTRAINT_GE;
    }
    pIdxInfo->estimatedRows = nRow;
    pIdxInfo->estimatedCost = 3.0 * (double)nRow;
    pIdxInfo->idxNum = idxNum;
  }

  return SQLITE_OK;
}

static int createUnionVtab(sqlite3 *db){
  static sqlite3_module unionModule = {
    0,                            /* iVersion */
    unionConnect,
    unionConnect,
    unionBestIndex,               /* xBestIndex - query planner */
    unionDisconnect, 
    unionDisconnect,
    unionOpen,                    /* xOpen - open a cursor */
    unionClose,                   /* xClose - close a cursor */
    unionFilter,                  /* xFilter - configure scan constraints */
    unionNext,                    /* xNext - advance a cursor */
    unionEof,                     /* xEof - check for end of scan */
    unionColumn,                  /* xColumn - read data */
    unionRowid,                   /* xRowid - read data */
    0,                            /* xUpdate */
    0,                            /* xBegin */
    0,                            /* xSync */
    0,                            /* xCommit */
    0,                            /* xRollback */
    0,                            /* xFindMethod */
    0,                            /* xRename */
  };

  return sqlite3_create_module(db, "unionvtab", &unionModule, 0);
}

#endif /* SQLITE_OMIT_VIRTUALTABLE */

#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_unionvtab_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
#ifndef SQLITE_OMIT_VIRTUALTABLE
  rc = createUnionVtab(db);
#endif
  return rc;
}

#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_UNIONVTAB) */

Changes to main.mk.

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  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/percentile.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/remember.c \
  $(TOP)/ext/misc/series.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/totype.c \

  $(TOP)/ext/misc/wholenumber.c \
  $(TOP)/ext/misc/vfslog.c \
  $(TOP)/ext/fts5/fts5_tcl.c \
  $(TOP)/ext/fts5/fts5_test_mi.c \
  $(TOP)/ext/fts5/fts5_test_tok.c 









>







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  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/percentile.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/remember.c \
  $(TOP)/ext/misc/series.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/totype.c \
  $(TOP)/ext/misc/unionvtab.c \
  $(TOP)/ext/misc/wholenumber.c \
  $(TOP)/ext/misc/vfslog.c \
  $(TOP)/ext/fts5/fts5_tcl.c \
  $(TOP)/ext/fts5/fts5_test_mi.c \
  $(TOP)/ext/fts5/fts5_test_tok.c 


Changes to src/pragma.c.

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  char *zSql;

  UNUSED_PARAMETER(idxNum);
  UNUSED_PARAMETER(idxStr);
  pragmaVtabCursorClear(pCsr);
  j = (pTab->pName->mPragFlg & PragFlg_Result1)!=0 ? 0 : 1;
  for(i=0; i<argc; i++, j++){

    assert( j<ArraySize(pCsr->azArg) );


    pCsr->azArg[j] = sqlite3_mprintf("%s", sqlite3_value_text(argv[i]));
    if( pCsr->azArg[j]==0 ){
      return SQLITE_NOMEM;

    }
  }
  sqlite3StrAccumInit(&acc, 0, 0, 0, pTab->db->aLimit[SQLITE_LIMIT_SQL_LENGTH]);
  sqlite3StrAccumAppendAll(&acc, "PRAGMA ");
  if( pCsr->azArg[1] ){
    sqlite3XPrintf(&acc, "%Q.", pCsr->azArg[1]);
  }







>

>
>
|
|
|
>







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  char *zSql;

  UNUSED_PARAMETER(idxNum);
  UNUSED_PARAMETER(idxStr);
  pragmaVtabCursorClear(pCsr);
  j = (pTab->pName->mPragFlg & PragFlg_Result1)!=0 ? 0 : 1;
  for(i=0; i<argc; i++, j++){
    const char *zText = (const char*)sqlite3_value_text(argv[i]);
    assert( j<ArraySize(pCsr->azArg) );
    assert( pCsr->azArg[j]==0 );
    if( zText ){
      pCsr->azArg[j] = sqlite3_mprintf("%s", zText);
      if( pCsr->azArg[j]==0 ){
        return SQLITE_NOMEM;
      }
    }
  }
  sqlite3StrAccumInit(&acc, 0, 0, 0, pTab->db->aLimit[SQLITE_LIMIT_SQL_LENGTH]);
  sqlite3StrAccumAppendAll(&acc, "PRAGMA ");
  if( pCsr->azArg[1] ){
    sqlite3XPrintf(&acc, "%Q.", pCsr->azArg[1]);
  }

Changes to src/test1.c.

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....
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  extern int sqlite3_percentile_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_regexp_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_remember_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_series_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_spellfix_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_totype_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_wholenumber_init(sqlite3*,char**,const sqlite3_api_routines*);

  static const struct {
    const char *zExtName;
    int (*pInit)(sqlite3*,char**,const sqlite3_api_routines*);
  } aExtension[] = {
    { "amatch",                sqlite3_amatch_init               },
    { "carray",                sqlite3_carray_init               },
    { "closure",               sqlite3_closure_init              },
................................................................................
    { "nextchar",              sqlite3_nextchar_init             },
    { "percentile",            sqlite3_percentile_init           },
    { "regexp",                sqlite3_regexp_init               },
    { "remember",              sqlite3_remember_init             },
    { "series",                sqlite3_series_init               },
    { "spellfix",              sqlite3_spellfix_init             },
    { "totype",                sqlite3_totype_init               },

    { "wholenumber",           sqlite3_wholenumber_init          },
  };
  sqlite3 *db;
  const char *zName;
  int i, j, rc;
  char *zErrMsg = 0;
  if( objc<3 ){







>







 







>







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  extern int sqlite3_percentile_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_regexp_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_remember_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_series_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_spellfix_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_totype_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_wholenumber_init(sqlite3*,char**,const sqlite3_api_routines*);
  extern int sqlite3_unionvtab_init(sqlite3*,char**,const sqlite3_api_routines*);
  static const struct {
    const char *zExtName;
    int (*pInit)(sqlite3*,char**,const sqlite3_api_routines*);
  } aExtension[] = {
    { "amatch",                sqlite3_amatch_init               },
    { "carray",                sqlite3_carray_init               },
    { "closure",               sqlite3_closure_init              },
................................................................................
    { "nextchar",              sqlite3_nextchar_init             },
    { "percentile",            sqlite3_percentile_init           },
    { "regexp",                sqlite3_regexp_init               },
    { "remember",              sqlite3_remember_init             },
    { "series",                sqlite3_series_init               },
    { "spellfix",              sqlite3_spellfix_init             },
    { "totype",                sqlite3_totype_init               },
    { "unionvtab",             sqlite3_unionvtab_init            },
    { "wholenumber",           sqlite3_wholenumber_init          },
  };
  sqlite3 *db;
  const char *zName;
  int i, j, rc;
  char *zErrMsg = 0;
  if( objc<3 ){

Added test/unionvtab.test.







































































































































































































































































































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# 2017-07-15
#
# 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.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is percentile.c extension
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix unionvtab

load_static_extension db unionvtab

#-------------------------------------------------------------------------
# Warm body tests.
#
forcedelete test.db2
do_execsql_test 1.0 {
  ATTACH 'test.db2' AS aux;

  CREATE TABLE t1(a INTEGER PRIMARY KEY, b TEXT);
  CREATE TABLE t2(a INTEGER PRIMARY KEY, b TEXT);
  CREATE TABLE aux.t3(a INTEGER PRIMARY KEY, b TEXT);


  INSERT INTO t1 VALUES(1, 'one'), (2, 'two'), (3, 'three');
  INSERT INTO t2 VALUES(10, 'ten'), (11, 'eleven'), (12, 'twelve');
  INSERT INTO t3 VALUES(20, 'twenty'), (21, 'twenty-one'), (22, 'twenty-two');
}

do_execsql_test 1.1 {
  CREATE VIRTUAL TABLE temp.uuu USING unionvtab(
    "VALUES(NULL, 't1', 1, 9),  ('main', 't2', 10, 19), ('aux', 't3', 20, 29)"
  );
  SELECT * FROM uuu;
} {
  1 one 2 two 3 three
  10 ten 11 eleven 12 twelve
  20 twenty 21 twenty-one 22 twenty-two
}

do_execsql_test 1.2 {
  PRAGMA table_info(uuu);
} {
  0 a INTEGER 0 {} 0 
  1 b TEXT 0 {} 0
}

do_execsql_test 1.3 {
  SELECT * FROM uuu WHERE rowid = 3;
  SELECT * FROM uuu WHERE rowid = 11;
} {3 three 11 eleven}

do_execsql_test 1.4 {
  SELECT * FROM uuu WHERE rowid IN (12, 10, 2);
} {2 two 10 ten 12 twelve}

do_execsql_test 1.5 {
  SELECT * FROM uuu WHERE rowid BETWEEN 3 AND 11;
} {3 three 10 ten 11 eleven}

do_execsql_test 1.6 {
  SELECT * FROM uuu WHERE rowid BETWEEN 11 AND 15;
} {11 eleven 12 twelve}

do_execsql_test 1.7 {
  SELECT * FROM uuu WHERE rowid BETWEEN -46 AND 1500;
} {
  1 one 2 two 3 three
  10 ten 11 eleven 12 twelve
  20 twenty 21 twenty-one 22 twenty-two
}

#-------------------------------------------------------------------------
# Error conditions.
#
#   2.1.*: Attempt to create a unionvtab table outside of the TEMP schema.
#   2.2.*: Tables that do not exist.
#   2.3.*: Non WITHOUT ROWID tables.
#   2.4.*: Tables with mismatched schemas.
#
do_catchsql_test 2.1.1 {
  CREATE VIRTUAL TABLE u1 USING unionvtab("VALUES(NULL, 't1', 1, 100)");
} {1 {unionvtab tables must be created in TEMP schema}}
do_catchsql_test 2.1.2 {
  CREATE VIRTUAL TABLE main.u1 USING unionvtab("VALUES('', 't1', 1, 100)");
} {1 {unionvtab tables must be created in TEMP schema}}
do_catchsql_test 2.1.3 {
  CREATE VIRTUAL TABLE aux.u1 USING unionvtab("VALUES('', 't1', 1, 100)");
} {1 {unionvtab tables must be created in TEMP schema}}

do_catchsql_test 2.2.1 {
  CREATE VIRTUAL TABLE temp.u1 USING unionvtab("VALUES(NULL, 't555', 1, 100)");
} {1 {no such table: t555}}
do_catchsql_test 2.2.2 {
  CREATE VIRTUAL TABLE temp.u1 USING unionvtab("VALUES('aux', 't555', 1, 100)");
} {1 {no such table: aux.t555}}
do_catchsql_test 2.2.3 {
  CREATE VIRTUAL TABLE temp.u1 USING unionvtab("VALUES('xua', 't555', 1, 100)");
} {1 {unknown database 'xua'}}

do_execsql_test 2.4.0 {
  CREATE TABLE x1(a BLOB, b);
  CREATE TABLE x2(a BLOB, b);
  CREATE TEMP TABLE x3(a BLOB, b);

  CREATE TABLE aux.y1(one, two, three INTEGER PRIMARY KEY);
  CREATE TEMP TABLE y2(one, two, three INTEGER PRIMARY KEY);
  CREATE TABLE y3(one, two, three INTEGER PRIMARY KEY);
}

foreach {tn dbs res} {
  1 {x1 x2 x3} {0 {}}
  2 {y1 y2 y3} {0 {}}
  3 {x1 y2 y3} {1 {source table schema mismatch}}
  4 {x1 y2 x3} {1 {source table schema mismatch}}
  5 {x1 x2 y3} {1 {source table schema mismatch}}
} {
  set L [list]
  set iMin 0
  foreach e $dbs {
    set E [split $e .]
    if {[llength $E]>1} {
      lappend L "('[lindex $E 0]', '[lindex $E 1]', $iMin, $iMin)"
    } else {
      lappend L "(NULL, '$e', $iMin, $iMin)"
    }
    incr iMin
  }

  set sql "CREATE VIRTUAL TABLE temp.a1 USING unionvtab(\"VALUES [join $L ,]\")"
  do_catchsql_test 2.4.$tn "
    DROP TABLE IF EXISTS temp.a1;
    CREATE VIRTUAL TABLE temp.a1 USING unionvtab(\"VALUES [join $L ,]\");
  " $res
}


finish_test