summaryrefslogtreecommitdiff
path: root/test/wordcount.c
blob: cf63e983c253e6f63071eabaa6801145151c863a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
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
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
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
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
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
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
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
406
407
408
409
410
411
412
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
/*
** This C program extracts all "words" from an input document and adds them
** to an SQLite database.  A "word" is any contiguous sequence of alphabetic
** characters.  All digits, punctuation, and whitespace characters are 
** word separators.  The database stores a single entry for each distinct
** word together with a count of the number of occurrences of that word.
** A fresh database is created automatically on each run.
**
**     wordcount DATABASE INPUTFILE
**
** The INPUTFILE name can be omitted, in which case input it taken from
** standard input.
**
** Option:
**
**     --without-rowid      Use a WITHOUT ROWID table to store the words.
**     --insert             Use INSERT mode (the default)
**     --replace            Use REPLACE mode
**     --select             Use SELECT mode
**     --update             Use UPDATE mode
**     --delete             Use DELETE mode
**     --query              Use QUERY mode
**     --nocase             Add the NOCASE collating sequence to the words.
**     --trace              Enable sqlite3_trace() output.
**     --summary            Show summary information on the collected data.
**     --stats              Show sqlite3_status() results at the end.
**     --pagesize NNN       Use a page size of NNN
**     --cachesize NNN      Use a cache size of NNN
**     --commit NNN         Commit after every NNN operations
**     --nosync             Use PRAGMA synchronous=OFF
**     --journal MMMM       Use PRAGMA journal_mode=MMMM
**     --timer              Time the operation of this program
**
** Modes:
**
** Insert mode means:
**    (1) INSERT OR IGNORE INTO wordcount VALUES($new,1)
**    (2) UPDATE wordcount SET cnt=cnt+1 WHERE word=$new -- if (1) is a noop
**
** Update mode means:
**    (1) INSERT OR IGNORE INTO wordcount VALUES($new,0)
**    (2) UPDATE wordcount SET cnt=cnt+1 WHERE word=$new
**
** Replace mode means:
**    (1) REPLACE INTO wordcount
**        VALUES($new,ifnull((SELECT cnt FROM wordcount WHERE word=$new),0)+1);
**
** Select mode means:
**    (1) SELECT 1 FROM wordcount WHERE word=$new
**    (2) INSERT INTO wordcount VALUES($new,1) -- if (1) returns nothing
**    (3) UPDATE wordcount SET cnt=cnt+1 WHERE word=$new  --if (1) return TRUE
**
** Delete mode means:
**    (1) DELETE FROM wordcount WHERE word=$new
**
** Query mode means:
**    (1) SELECT cnt FROM wordcount WHERE word=$new
**
** Note that delete mode and query mode are only useful for preexisting
** databases.  The wordcount table is created using IF NOT EXISTS so this
** utility can be run multiple times on the same database file.  The
** --without-rowid, --nocase, and --pagesize parameters are only effective
** when creating a new database and are harmless no-ops on preexisting
** databases.
**
******************************************************************************
**
** Compile as follows:
**
**    gcc -I. wordcount.c sqlite3.c -ldl -lpthreads
**
** Or:
**
**    gcc -I. -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION \
**        wordcount.c sqlite3.c
*/
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include <stdarg.h>
#include "sqlite3.h"

/* Return the current wall-clock time */
static sqlite3_int64 realTime(void){
  static sqlite3_vfs *clockVfs = 0;
  sqlite3_int64 t;
  if( clockVfs==0 ) clockVfs = sqlite3_vfs_find(0);
  if( clockVfs->iVersion>=1 && clockVfs->xCurrentTimeInt64!=0 ){
    clockVfs->xCurrentTimeInt64(clockVfs, &t);
  }else{
    double r;
    clockVfs->xCurrentTime(clockVfs, &r);
    t = (sqlite3_int64)(r*86400000.0);
  }
  return t;
}

/* Print an error message and exit */
static void fatal_error(const char *zMsg, ...){
  va_list ap;
  va_start(ap, zMsg);
  vfprintf(stderr, zMsg, ap);
  va_end(ap);
  exit(1);
}

/* The sqlite3_trace() callback function */
static void traceCallback(void *NotUsed, const char *zSql){
  printf("%s;\n", zSql);
}

/* An sqlite3_exec() callback that prints results on standard output,
** each column separated by a single space. */
static int printResult(void *NotUsed, int nArg, char **azArg, char **azNm){
  int i;
  printf("--");
  for(i=0; i<nArg; i++){
    printf(" %s", azArg[i] ? azArg[i] : "(null)");
  }
  printf("\n");
  return 0;
}


/*
** Add one character to a hash
*/
static void addCharToHash(unsigned int *a, unsigned char x){
  if( a[0]<4 ){
    a[1] = (a[1]<<8) | x;
    a[0]++;
  }else{
    a[2] = (a[2]<<8) | x;
    a[0]++;
    if( a[0]==8 ){
      a[3] += a[1] + a[4];
      a[4] += a[2] + a[3];
      a[0] = a[1] = a[2] = 0;
    }
  }    
}

/*
** Compute the final hash value.
*/
static void finalHash(unsigned int *a, char *z){
  a[3] += a[1] + a[4] + a[0];
  a[4] += a[2] + a[3];
  sqlite3_snprintf(17, z, "%08x%08x", a[3], a[4]);
}


/*
** Implementation of a checksum() aggregate SQL function
*/
static void checksumStep(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const unsigned char *zVal;
  int nVal, i, j;
  unsigned int *a;
  a = (unsigned*)sqlite3_aggregate_context(context, sizeof(unsigned int)*5);

  if( a ){
    for(i=0; i<argc; i++){
      nVal = sqlite3_value_bytes(argv[i]);
      zVal = (const unsigned char*)sqlite3_value_text(argv[i]);
      if( zVal ) for(j=0; j<nVal; j++) addCharToHash(a, zVal[j]);
      addCharToHash(a, '|');
    }
    addCharToHash(a, '\n');
  }
}
static void checksumFinalize(sqlite3_context *context){
  unsigned int *a;
  char zResult[24];
  a = sqlite3_aggregate_context(context, 0);
  if( a ){
    finalHash(a, zResult);
    sqlite3_result_text(context, zResult, -1, SQLITE_TRANSIENT);
  }
}


/* Define operating modes */
#define MODE_INSERT     0
#define MODE_REPLACE    1
#define MODE_SELECT     2
#define MODE_UPDATE     3
#define MODE_DELETE     4
#define MODE_QUERY      5

int main(int argc, char **argv){
  const char *zFileToRead = 0;  /* Input file.  NULL for stdin */
  const char *zDbName = 0;      /* Name of the database file to create */
  int useWithoutRowid = 0;      /* True for --without-rowid */
  int iMode = MODE_INSERT;      /* One of MODE_xxxxx */
  int useNocase = 0;            /* True for --nocase */
  int doTrace = 0;              /* True for --trace */
  int showStats = 0;            /* True for --stats */
  int showSummary = 0;          /* True for --summary */
  int showTimer = 0;            /* True for --timer */
  int cacheSize = 0;            /* Desired cache size.  0 means default */
  int pageSize = 0;             /* Desired page size.  0 means default */
  int commitInterval = 0;       /* How often to commit.  0 means never */
  int noSync = 0;               /* True for --nosync */
  const char *zJMode = 0;       /* Journal mode */
  int nOp = 0;                  /* Operation counter */
  int i, j;                     /* Loop counters */
  sqlite3 *db;                  /* The SQLite database connection */
  char *zSql;                   /* Constructed SQL statement */
  sqlite3_stmt *pInsert = 0;    /* The INSERT statement */
  sqlite3_stmt *pUpdate = 0;    /* The UPDATE statement */
  sqlite3_stmt *pSelect = 0;    /* The SELECT statement */
  sqlite3_stmt *pDelete = 0;    /* The DELETE statement */
  FILE *in;                     /* The open input file */
  int rc;                       /* Return code from an SQLite interface */
  int iCur, iHiwtr;             /* Statistics values, current and "highwater" */
  sqlite3_int64 sumCnt = 0;     /* Sum in QUERY mode */
  sqlite3_int64 startTime;
  char zInput[2000];            /* A single line of input */

  /* Process command-line arguments */
  for(i=1; i<argc; i++){
    const char *z = argv[i];
    if( z[0]=='-' ){
      do{ z++; }while( z[0]=='-' );
      if( strcmp(z,"without-rowid")==0 ){
        useWithoutRowid = 1;
      }else if( strcmp(z,"replace")==0 ){
        iMode = MODE_REPLACE;
      }else if( strcmp(z,"select")==0 ){
        iMode = MODE_SELECT;
      }else if( strcmp(z,"insert")==0 ){
        iMode = MODE_INSERT;
      }else if( strcmp(z,"update")==0 ){
        iMode = MODE_UPDATE;
      }else if( strcmp(z,"delete")==0 ){
        iMode = MODE_DELETE;
      }else if( strcmp(z,"query")==0 ){
        iMode = MODE_QUERY;
      }else if( strcmp(z,"nocase")==0 ){
        useNocase = 1;
      }else if( strcmp(z,"trace")==0 ){
        doTrace = 1;
      }else if( strcmp(z,"nosync")==0 ){
        noSync = 1;
      }else if( strcmp(z,"stats")==0 ){
        showStats = 1;
      }else if( strcmp(z,"summary")==0 ){
        showSummary = 1;
      }else if( strcmp(z,"timer")==0 ){
        showTimer = i;
      }else if( strcmp(z,"cachesize")==0 && i<argc-1 ){
        i++;
        cacheSize = atoi(argv[i]);
      }else if( strcmp(z,"pagesize")==0 && i<argc-1 ){
        i++;
        pageSize = atoi(argv[i]);
      }else if( strcmp(z,"commit")==0 && i<argc-1 ){
        i++;
        commitInterval = atoi(argv[i]);
      }else if( strcmp(z,"journal")==0 && i<argc-1 ){
        zJMode = argv[++i];
      }else{
        fatal_error("unknown option: %s\n", argv[i]);
      }
    }else if( zDbName==0 ){
      zDbName = argv[i];
    }else if( zFileToRead==0 ){
      zFileToRead = argv[i];
    }else{
      fatal_error("surplus argument: %s\n", argv[i]);
    }
  }
  if( zDbName==0 ){
    fatal_error("Usage: %s [--options] DATABASE [INPUTFILE]\n", argv[0]);
  }
  startTime = realTime();

  /* Open the database and the input file */
  if( sqlite3_open(zDbName, &db) ){
    fatal_error("Cannot open database file: %s\n", zDbName);
  }
  if( zFileToRead ){
    in = fopen(zFileToRead, "rb");
    if( in==0 ){
      fatal_error("Could not open input file \"%s\"\n", zFileToRead);
    }
  }else{
    in = stdin;
  }

  /* Set database connection options */
  if( doTrace ) sqlite3_trace(db, traceCallback, 0);
  if( pageSize ){
    zSql = sqlite3_mprintf("PRAGMA page_size=%d", pageSize);
    sqlite3_exec(db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }
  if( cacheSize ){
    zSql = sqlite3_mprintf("PRAGMA cache_size=%d", cacheSize);
    sqlite3_exec(db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }
  if( noSync ) sqlite3_exec(db, "PRAGMA synchronous=OFF", 0, 0, 0);
  if( zJMode ){
    zSql = sqlite3_mprintf("PRAGMA journal_mode=%s", zJMode);
    sqlite3_exec(db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }


  /* Construct the "wordcount" table into which to put the words */
  if( sqlite3_exec(db, "BEGIN IMMEDIATE", 0, 0, 0) ){
    fatal_error("Could not start a transaction\n");
  }
  zSql = sqlite3_mprintf(
     "CREATE TABLE IF NOT EXISTS wordcount(\n"
     "  word TEXT PRIMARY KEY COLLATE %s,\n"
     "  cnt INTEGER\n"
     ")%s",
     useNocase ? "nocase" : "binary",
     useWithoutRowid ? " WITHOUT ROWID" : ""
  );
  if( zSql==0 ) fatal_error("out of memory\n");
  rc = sqlite3_exec(db, zSql, 0, 0, 0);
  if( rc ) fatal_error("Could not create the wordcount table: %s.\n",
                       sqlite3_errmsg(db));
  sqlite3_free(zSql);

  /* Prepare SQL statements that will be needed */
  if( iMode==MODE_QUERY ){
    rc = sqlite3_prepare_v2(db,
          "SELECT cnt FROM wordcount WHERE word=?1",
          -1, &pSelect, 0);
    if( rc ) fatal_error("Could not prepare the SELECT statement: %s\n",
                          sqlite3_errmsg(db));
  }
  if( iMode==MODE_SELECT ){
    rc = sqlite3_prepare_v2(db,
          "SELECT 1 FROM wordcount WHERE word=?1",
          -1, &pSelect, 0);
    if( rc ) fatal_error("Could not prepare the SELECT statement: %s\n",
                          sqlite3_errmsg(db));
    rc = sqlite3_prepare_v2(db,
          "INSERT INTO wordcount(word,cnt) VALUES(?1,1)",
          -1, &pInsert, 0);
    if( rc ) fatal_error("Could not prepare the INSERT statement: %s\n",
                         sqlite3_errmsg(db));
  }
  if( iMode==MODE_SELECT || iMode==MODE_UPDATE || iMode==MODE_INSERT ){
    rc = sqlite3_prepare_v2(db,
          "UPDATE wordcount SET cnt=cnt+1 WHERE word=?1",
          -1, &pUpdate, 0);
    if( rc ) fatal_error("Could not prepare the UPDATE statement: %s\n",
                         sqlite3_errmsg(db));
  }
  if( iMode==MODE_INSERT ){
    rc = sqlite3_prepare_v2(db,
          "INSERT OR IGNORE INTO wordcount(word,cnt) VALUES(?1,1)",
          -1, &pInsert, 0);
    if( rc ) fatal_error("Could not prepare the INSERT statement: %s\n",
                         sqlite3_errmsg(db));
  }
  if( iMode==MODE_UPDATE ){
    rc = sqlite3_prepare_v2(db,
          "INSERT OR IGNORE INTO wordcount(word,cnt) VALUES(?1,0)",
          -1, &pInsert, 0);
    if( rc ) fatal_error("Could not prepare the INSERT statement: %s\n",
                         sqlite3_errmsg(db));
  }
  if( iMode==MODE_REPLACE ){
    rc = sqlite3_prepare_v2(db,
          "REPLACE INTO wordcount(word,cnt)"
          "VALUES(?1,coalesce((SELECT cnt FROM wordcount WHERE word=?1),0)+1)",
          -1, &pInsert, 0);
    if( rc ) fatal_error("Could not prepare the REPLACE statement: %s\n",
                          sqlite3_errmsg(db));
  }
  if( iMode==MODE_DELETE ){
    rc = sqlite3_prepare_v2(db,
          "DELETE FROM wordcount WHERE word=?1",
          -1, &pDelete, 0);
    if( rc ) fatal_error("Could not prepare the DELETE statement: %s\n",
                         sqlite3_errmsg(db));
  }

  /* Process the input file */
  while( fgets(zInput, sizeof(zInput), in) ){
    for(i=0; zInput[i]; i++){
      if( !isalpha(zInput[i]) ) continue;
      for(j=i+1; isalpha(zInput[j]); j++){}

      /* Found a new word at zInput[i] that is j-i bytes long. 
      ** Process it into the wordcount table.  */
      if( iMode==MODE_DELETE ){
        sqlite3_bind_text(pDelete, 1, zInput+i, j-i, SQLITE_STATIC);
        if( sqlite3_step(pDelete)!=SQLITE_DONE ){
          fatal_error("DELETE failed: %s\n", sqlite3_errmsg(db));
        }
        sqlite3_reset(pDelete);
      }else if( iMode==MODE_SELECT ){
        sqlite3_bind_text(pSelect, 1, zInput+i, j-i, SQLITE_STATIC);
        rc = sqlite3_step(pSelect);
        sqlite3_reset(pSelect);
        if( rc==SQLITE_ROW ){
          sqlite3_bind_text(pUpdate, 1, zInput+i, j-i, SQLITE_STATIC);
          if( sqlite3_step(pUpdate)!=SQLITE_DONE ){
            fatal_error("UPDATE failed: %s\n", sqlite3_errmsg(db));
          }
          sqlite3_reset(pUpdate);
        }else if( rc==SQLITE_DONE ){
          sqlite3_bind_text(pInsert, 1, zInput+i, j-i, SQLITE_STATIC);
          if( sqlite3_step(pInsert)!=SQLITE_DONE ){
            fatal_error("Insert failed: %s\n", sqlite3_errmsg(db));
          }
          sqlite3_reset(pInsert);
        }else{
          fatal_error("SELECT failed: %s\n", sqlite3_errmsg(db));
        }
      }else if( iMode==MODE_QUERY ){
        sqlite3_bind_text(pSelect, 1, zInput+i, j-i, SQLITE_STATIC);
        if( sqlite3_step(pSelect)==SQLITE_ROW ){
          sumCnt += sqlite3_column_int64(pSelect, 0);
        }
        sqlite3_reset(pSelect);
      }else{
        sqlite3_bind_text(pInsert, 1, zInput+i, j-i, SQLITE_STATIC);
        if( sqlite3_step(pInsert)!=SQLITE_DONE ){
          fatal_error("INSERT failed: %s\n", sqlite3_errmsg(db));
        }
        sqlite3_reset(pInsert);
        if( iMode==MODE_UPDATE
         || (iMode==MODE_INSERT && sqlite3_changes(db)==0)
        ){
          sqlite3_bind_text(pUpdate, 1, zInput+i, j-i, SQLITE_STATIC);
          if( sqlite3_step(pUpdate)!=SQLITE_DONE ){
            fatal_error("UPDATE failed: %s\n", sqlite3_errmsg(db));
          }
          sqlite3_reset(pUpdate);
        }
      }
      i = j-1;

      /* Increment the operation counter.  Do a COMMIT if it is time. */
      nOp++;
      if( commitInterval>0 && (nOp%commitInterval)==0 ){
        sqlite3_exec(db, "COMMIT; BEGIN IMMEDIATE", 0, 0, 0);
      }
    }
  }
  sqlite3_exec(db, "COMMIT", 0, 0, 0);
  if( zFileToRead ) fclose(in);
  sqlite3_finalize(pInsert);
  sqlite3_finalize(pUpdate);
  sqlite3_finalize(pSelect);
  sqlite3_finalize(pDelete);

  if( iMode==MODE_QUERY ){
    printf("sum of cnt: %lld\n", sumCnt);
    rc = sqlite3_prepare_v2(db,"SELECT sum(cnt*cnt) FROM wordcount", -1,
                            &pSelect, 0);
    if( rc==SQLITE_OK && sqlite3_step(pSelect)==SQLITE_ROW ){
      printf("double-check: %lld\n", sqlite3_column_int64(pSelect, 0));
    }
    sqlite3_finalize(pSelect);
  }


  if( showTimer ){
    sqlite3_int64 elapseTime = realTime() - startTime;
    fprintf(stderr, "%3d.%03d wordcount", (int)(elapseTime/1000),
                                   (int)(elapseTime%1000));
    for(i=1; i<argc; i++) if( i!=showTimer ) fprintf(stderr, " %s", argv[i]);
    fprintf(stderr, "\n");
  }

  if( showSummary ){
    sqlite3_create_function(db, "checksum", -1, SQLITE_UTF8, 0,
                            0, checksumStep, checksumFinalize);
    sqlite3_exec(db, 
      "SELECT 'count(*):  ', count(*) FROM wordcount;\n"
      "SELECT 'sum(cnt):  ', sum(cnt) FROM wordcount;\n"
      "SELECT 'max(cnt):  ', max(cnt) FROM wordcount;\n"
      "SELECT 'avg(cnt):  ', avg(cnt) FROM wordcount;\n"
      "SELECT 'sum(cnt=1):', sum(cnt=1) FROM wordcount;\n"
      "SELECT 'top 10:    ', group_concat(word, ', ') FROM "
         "(SELECT word FROM wordcount ORDER BY cnt DESC, word LIMIT 10);\n"
      "SELECT 'checksum:  ', checksum(word, cnt) FROM "
         "(SELECT word, cnt FROM wordcount ORDER BY word);\n"
      "PRAGMA integrity_check;\n",
      printResult, 0, 0);
  }

  /* Database connection statistics printed after both prepared statements
  ** have been finalized */
  if( showStats ){
    sqlite3_db_status(db, SQLITE_DBSTATUS_LOOKASIDE_USED, &iCur, &iHiwtr, 0);
    printf("-- Lookaside Slots Used:        %d (max %d)\n", iCur,iHiwtr);
    sqlite3_db_status(db, SQLITE_DBSTATUS_LOOKASIDE_HIT, &iCur, &iHiwtr, 0);
    printf("-- Successful lookasides:       %d\n", iHiwtr);
    sqlite3_db_status(db, SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE, &iCur,&iHiwtr,0);
    printf("-- Lookaside size faults:       %d\n", iHiwtr);
    sqlite3_db_status(db, SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL, &iCur,&iHiwtr,0);
    printf("-- Lookaside OOM faults:        %d\n", iHiwtr);
    sqlite3_db_status(db, SQLITE_DBSTATUS_CACHE_USED, &iCur, &iHiwtr, 0);
    printf("-- Pager Heap Usage:            %d bytes\n", iCur);
    sqlite3_db_status(db, SQLITE_DBSTATUS_CACHE_HIT, &iCur, &iHiwtr, 1);
    printf("-- Page cache hits:             %d\n", iCur);
    sqlite3_db_status(db, SQLITE_DBSTATUS_CACHE_MISS, &iCur, &iHiwtr, 1);
    printf("-- Page cache misses:           %d\n", iCur); 
    sqlite3_db_status(db, SQLITE_DBSTATUS_CACHE_WRITE, &iCur, &iHiwtr, 1);
    printf("-- Page cache writes:           %d\n", iCur); 
    sqlite3_db_status(db, SQLITE_DBSTATUS_SCHEMA_USED, &iCur, &iHiwtr, 0);
    printf("-- Schema Heap Usage:           %d bytes\n", iCur); 
    sqlite3_db_status(db, SQLITE_DBSTATUS_STMT_USED, &iCur, &iHiwtr, 0);
    printf("-- Statement Heap Usage:        %d bytes\n", iCur); 
  }

  sqlite3_close(db);

  /* Global memory usage statistics printed after the database connection
  ** has closed.  Memory usage should be zero at this point. */
  if( showStats ){
    sqlite3_status(SQLITE_STATUS_MEMORY_USED, &iCur, &iHiwtr, 0);
    printf("-- Memory Used (bytes):         %d (max %d)\n", iCur,iHiwtr);
    sqlite3_status(SQLITE_STATUS_MALLOC_COUNT, &iCur, &iHiwtr, 0);
    printf("-- Outstanding Allocations:     %d (max %d)\n", iCur,iHiwtr);
    sqlite3_status(SQLITE_STATUS_PAGECACHE_OVERFLOW, &iCur, &iHiwtr, 0);
    printf("-- Pcache Overflow Bytes:       %d (max %d)\n", iCur,iHiwtr);
    sqlite3_status(SQLITE_STATUS_SCRATCH_OVERFLOW, &iCur, &iHiwtr, 0);
    printf("-- Scratch Overflow Bytes:      %d (max %d)\n", iCur,iHiwtr);
    sqlite3_status(SQLITE_STATUS_MALLOC_SIZE, &iCur, &iHiwtr, 0);
    printf("-- Largest Allocation:          %d bytes\n",iHiwtr);
    sqlite3_status(SQLITE_STATUS_PAGECACHE_SIZE, &iCur, &iHiwtr, 0);
    printf("-- Largest Pcache Allocation:   %d bytes\n",iHiwtr);
    sqlite3_status(SQLITE_STATUS_SCRATCH_SIZE, &iCur, &iHiwtr, 0);
    printf("-- Largest Scratch Allocation:  %d bytes\n", iHiwtr);
  }
  return 0;
}