SQLite

end_diff_one_table:
  strFree(&sql);
  sqlite3_free(zId);
  namelistFree(az);
  namelistFree(az2);
  return;
}

/*
** Write a 64-bit signed integer as a varint onto out
*/
static void putsVarint(FILE *out, sqlite3_uint64 v){
  int i, n;
  unsigned char buf[12], p[12];
  if( v & (((sqlite3_uint64)0xff000000)<<32) ){
    p[8] = (unsigned char)v;
    v >>= 8;
    for(i=7; i>=0; i--){
      p[i] = (unsigned char)((v & 0x7f) | 0x80);
      v >>= 7;
    }
    fwrite(p, 8, 1, out);
  }else{
    n = 9;
    do{
      p[n--] = (unsigned char)((v & 0x7f) | 0x80);
      v >>= 7;
    }while( v!=0 );
    buf[9] &= 0x7f;
    fwrite(buf+n+1, 9-n, 1, out);
  }
}

/*
** Generate a CHANGESET for all differences from main.zTab to aux.zTab.
*/
static void changeset_one_table(const char *zTab, FILE *out){
  sqlite3_stmt *pStmt;          /* SQL statment */
  char *zId = safeId(zTab);     /* Escaped name of the table */
  char **azCol = 0;             /* List of escaped column names */
  int nCol = 0;                 /* Number of columns */
  int *aiFlg = 0;               /* 0 if column is not part of PK */
  int *aiPk = 0;                /* Column numbers for each PK column */
  int nPk = 0;                  /* Number of PRIMARY KEY columns */
  Str sql;                      /* SQL for the diff query */
  int i, j;                     /* Loop counters */
  const char *zSep;             /* List separator */

  pStmt = db_prepare(
      "SELECT A.sql=B.sql FROM main.sqlite_master A, aux.sqlite_master B"
      " WHERE A.name=%Q AND B.name=%Q", zTab, zTab
  );
  if( SQLITE_ROW==sqlite3_step(pStmt) ){

      aiPk[i-1] = nCol-1;
    }
  }
  sqlite3_finalize(pStmt);
  if( nPk==0 ) goto end_changeset_one_table; 
  strInit(&sql);
  if( nCol>nPk ){
    strPrintf(&sql, "SELECT %d", SQLITE_UPDATE);
    for(i=0; i<nCol; i++) strPrintf(&sql, ", A.%s", azCol[i]);
    for(i=0; i<nCol; i++) strPrintf(&sql, ", B.%s", azCol[i]);
    strPrintf(&sql,"\n  FROM main.%s A, aux.%s B\n", zId, zId);
    zSep = " WHERE";
    for(i=0; i<nPk; i++){
      strPrintf(&sql, "%s A.%s=B.%s", zSep, azCol[aiPk[i]], azCol[aiPk[i]]);
      zSep = " AND";
    }
    zSep = "\n   AND (";
    for(i=0; i<nCol; i++){
      if( aiFlg[i] ) continue;
      strPrintf(&sql, "%sA.%s IS NOT B.%s", zSep, azCol[i], azCol[i]);
      zSep = " OR\n        ";
    }
    strPrintf(&sql,")\n UNION ALL\n");
  }
  strPrintf(&sql, "SELECT %d", SQLITE_DELETE);
  for(i=0; i<nCol; i++) strPrintf(&sql, ", A.%s", azCol[i]);
  for(i=0; i<nCol; i++) strPrintf(&sql, ", 0");
  strPrintf(&sql, "  FROM main.%s A\n", zId);
  strPrintf(&sql, " WHERE NOT EXISTS(SELECT 1 FROM aux.%s B\n", zId);
  zSep =          "                   WHERE";
  for(i=0; i<nPk; i++){
    strPrintf(&sql, "%s A.%s=B.%s", zSep, azCol[aiPk[i]], azCol[aiPk[i]]);
    zSep = " AND";
  }
  strPrintf(&sql, ")\n UNION ALL\n");
  strPrintf(&sql, "SELECT %d", SQLITE_INSERT);
  for(i=0; i<nCol; i++) strPrintf(&sql, ", 0");
  for(i=0; i<nCol; i++) strPrintf(&sql, ", B.%s", azCol[i]);
  strPrintf(&sql, "  FROM aux.%s B\n", zId);
  strPrintf(&sql, " WHERE NOT EXISTS(SELECT 1 FROM main.%s A\n", zId);
  zSep =          "                   WHERE";
  for(i=0; i<nPk; i++){
    strPrintf(&sql, "%s A.%s=B.%s", zSep, azCol[aiPk[i]], azCol[aiPk[i]]);
    zSep = " AND";
  }
  strPrintf(&sql, ")\n");
  strPrintf(&sql, " ORDER BY");
  zSep = " ";
  for(i=0; i<nPk; i++){
    strPrintf(&sql, "%s %d", zSep, aiPk[i]+1);
    zSep = ",";
  }
  strPrintf(&sql, ";\n");

  if( g.fDebug & DEBUG_DIFF_SQL ){ 
    printf("SQL for %s:\n%s\n", zId, sql.z);
    goto end_changeset_one_table;
  }

  putc('T', out);
  putsVarint(out, (sqlite3_uint64)nCol);
  for(i=0; i<nCol; i++) putc(aiFlg[i]!=0, out);
  fwrite(zTab, 1, strlen(zTab), out);
  putc(0, out);

  pStmt = db_prepare("%s", sql.z);
  while( SQLITE_ROW==sqlite3_step(pStmt) ){
    int iType = sqlite3_column_int(pStmt,0);
    int iFirst = iType==SQLITE_INSERT ? nCol+1 : 1;
    int iLast = iType==SQLITE_DELETE ? nCol+1 : 2*nCol+1;
    putc(iType, out);
    putc(0, out);
    for(i=iFirst; i<=iLast; i++){
      int iDType = sqlite3_column_type(pStmt,i);
      sqlite3_int64 iX;
      double rX;
      sqlite3_uint64 uX;
      putc(iDType, out);
      switch( iDType ){
        case SQLITE_INTEGER:
          iX = sqlite3_column_int64(pStmt,i);
          memcpy(&uX, &iX, 8);
          for(j=56; j>=0; j-=8) putc((uX>>j)&0xff, out);
          break;
        case SQLITE_FLOAT:
          rX = sqlite3_column_int64(pStmt,i);
          memcpy(&uX, &rX, 8);
          for(j=56; j>=0; j-=8) putc((uX>>j)&0xff, out);
          break;
        case SQLITE_TEXT:
          iX = sqlite3_column_bytes(pStmt,i);
          putsVarint(out, (sqlite3_uint64)iX);
          fwrite(sqlite3_column_text(pStmt,i),1,iX,out);
          break;
        case SQLITE_BLOB:
          iX = sqlite3_column_bytes(pStmt,i);
          putsVarint(out, (sqlite3_uint64)iX);
          fwrite(sqlite3_column_blob(pStmt,i),1,iX,out);
          break;
        case SQLITE_NULL:
          break;
      }
    }
  }
  sqlite3_finalize(pStmt);
  
end_changeset_one_table:
  while( nCol>0 ) sqlite3_free(azCol[--nCol]);
  sqlite3_free(azCol);
  sqlite3_free(aiPk);
  sqlite3_free(zId);
}