src/shell.c

/*
** Copyright (c) 1999, 2000 D. Richard Hipp
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public
** License as published by the Free Software Foundation; either
** version 2 of the License, or (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
** General Public License for more details.
** 
** You should have received a copy of the GNU General Public
** License along with this library; if not, write to the
** Free Software Foundation, Inc., 59 Temple Place - Suite 330,
** Boston, MA  02111-1307, USA.
**
** Author contact information:
**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*************************************************************************
** This file contains code to implement the "sqlite" command line
** utility for accessing SQLite databases.
**
** $Id: shell.c,v 1.25 2000/09/29 13:30:55 drh Exp $
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "sqlite.h"
#include <unistd.h>
#include <ctype.h>

#if defined(HAVE_READLINE) && HAVE_READLINE==1
# include <readline/readline.h>
# include <readline/history.h>
#else
# define readline getline
# define add_history(X) 
#endif

/*
** This routine reads a line of text from standard input, stores
** the text in memory obtained from malloc() and returns a pointer
** to the text.  NULL is returned at end of file, or if malloc()
** fails.
**
** The interface is like "readline" but no command-line editing
** is done.
*/
static char *getline(char *zPrompt){
  char *zLine;
  int nLine;
  int n;
  int eol;

  if( zPrompt && *zPrompt ){
    printf("%s",zPrompt);
    fflush(stdout);
  }
  nLine = 100;
  zLine = malloc( nLine );
  if( zLine==0 ) return 0;
  n = 0;
  eol = 0;
  while( !eol ){
    if( n+100>nLine ){
      nLine = nLine*2 + 100;
      zLine = realloc(zLine, nLine);
      if( zLine==0 ) return 0;
    }
    if( fgets(&zLine[n], nLine - n, stdin)==0 ){
      if( n==0 ){
        free(zLine);
        return 0;
      }
      zLine[n] = 0;
      eol = 1;
      break;
    }
    while( zLine[n] ){ n++; }
    if( n>0 && zLine[n-1]=='\n' ){
      n--;
      zLine[n] = 0;
      eol = 1;
    }
  }
  zLine = realloc( zLine, n+1 );
  return zLine;
}

/*
** Retrieve a single line of input text.  "isatty" is true if text
** is coming from a terminal.  In that case, we issue a prompt and
** attempt to use "readline" for command-line editing.  If "isatty"
** is false, use "getline" instead of "readline" and issue to prompt.
**
** zPrior is a string of prior text retrieved.  If not the empty
** string, then issue a continuation prompt.
*/
static char *one_input_line(const char *zPrior, int isatty){
  char *zPrompt;
  char *zResult;
  if( !isatty ){
    return getline(0);
  }
  if( zPrior && zPrior[0] ){
    zPrompt = "   ...> ";
  }else{
    zPrompt = "sqlite> ";
  }
  zResult = readline(zPrompt);
  if( zResult ) add_history(zResult);
  return zResult;
}

/*
** An pointer to an instance of this structure is passed from
** the main program to the callback.  This is used to communicate
** state and mode information.
*/
struct callback_data {
  sqlite *db;            /* The database */
  int cnt;               /* Number of records displayed so far */
  FILE *out;             /* Write results here */
  int mode;              /* An output mode setting */
  int showHeader;        /* True to show column names in List or Column mode */
  int escape;            /* Escape this character when in MODE_List */
  char zDestTable[250];  /* Name of destination table when MODE_Insert */
  char separator[20];    /* Separator character for MODE_List */
  int colWidth[100];     /* Requested width of each column when in column mode*/
  int actualWidth[100];  /* Actual width of each column */
};

/*
** These are the allowed modes.
*/
#define MODE_Line     0  /* One column per line.  Blank line between records */
#define MODE_Column   1  /* One record per line in neat columns */
#define MODE_List     2  /* One record per line with a separator */
#define MODE_Semi     3  /* Same as MODE_List but append ";" to each line */
#define MODE_Html     4  /* Generate an XHTML table */
#define MODE_Insert   5  /* Generate SQL "insert" statements */

/*
** Number of elements in an array
*/
#define ArraySize(X)  (sizeof(X)/sizeof(X[0]))

/*
** Return TRUE if the string supplied is a number of some kinds.
*/
static int is_numeric(const char *z){
  int seen_digit = 0;
  if( *z=='-' || *z=='+' ){
    z++;
  }
  while( isdigit(*z) ){ 
    seen_digit = 1;
    z++;
  }
  if( seen_digit && *z=='.' ){
    z++;
    while( isdigit(*z) ){ z++; }
  }
  if( seen_digit && (*z=='e' || *z=='E')
   && (isdigit(z[1]) || ((z[1]=='-' || z[1]=='+') && isdigit(z[2])))
  ){
    z+=2;
    while( isdigit(*z) ){ z++; }
  }
  return seen_digit && *z==0;
}

/*
** Output the given string as a quoted string using SQL quoting conventions.
*/
static void output_quoted_string(FILE *out, const char *z){
  int i;
  int nSingle = 0;
  int nDouble = 0;
  for(i=0; z[i]; i++){
    if( z[i]=='\'' ) nSingle++;
    else if( z[i]=='"' ) nDouble++;
  }
  if( nSingle==0 ){
    fprintf(out,"'%s'",z);
  }else if( nDouble==0 ){
    fprintf(out,"\"%s\"",z);
  }else{
    fprintf(out,"'");
    while( *z ){
      for(i=0; z[i] && z[i]!='\''; i++){}
      if( i==0 ){
        fprintf(out,"''");
        z++;
      }else if( z[i]=='\'' ){
        fprintf(out,"%.*s''",i,z);
        z += i+1;
      }else{
        fprintf(out,"%s'",z);
        break;
      }
    }
  }
}

/*
** Output the given string with characters that are special to
** HTML escaped.
*/
static void output_html_string(FILE *out, const char *z){
  int i;
  while( *z ){
    for(i=0; z[i] && z[i]!='<' && z[i]!='&'; i++){}
    if( i>0 ){
      fprintf(out,"%.*s",i,z);
    }
    if( z[i]=='<' ){
      fprintf(out,"&lt;");
    }else if( z[i]=='&' ){
      fprintf(out,"&amp;");
    }else{
      break;
    }
    z += i + 1;
  }
}

/*
** This is the callback routine that the SQLite library
** invokes for each row of a query result.
*/
static int callback(void *pArg, int nArg, char **azArg, char **azCol){
  int i;
  struct callback_data *p = (struct callback_data*)pArg;
  switch( p->mode ){
    case MODE_Line: {
      int w = 5;
      for(i=0; i<nArg; i++){
        int len = strlen(azCol[i]);
        if( len>w ) w = len;
      }
      if( p->cnt++>0 ) fprintf(p->out,"\n");
      for(i=0; i<nArg; i++){
        fprintf(p->out,"%*s = %s\n", w, azCol[i], azArg[i] ? azArg[i] : 0);
      }
      break;
    }
    case MODE_Column: {
      if( p->cnt++==0 ){
        for(i=0; i<nArg; i++){
          int w, n;
          if( i<ArraySize(p->colWidth) ){
             w = p->colWidth[i];
          }else{
             w = 0;
          }
          if( w<=0 ){
            w = strlen(azCol[i] ? azCol[i] : "");
            if( w<10 ) w = 10;
            n = strlen(azArg[i] ? azArg[i] : "");
            if( w<n ) w = n;
          }
          if( i<ArraySize(p->actualWidth) ){
            p->actualWidth[i] = w; 
          }
          if( p->showHeader ){
            fprintf(p->out,"%-*.*s%s",w,w,azCol[i], i==nArg-1 ? "\n": "  ");
          }
        }
        if( p->showHeader ){
          for(i=0; i<nArg; i++){
            int w;
            if( i<ArraySize(p->actualWidth) ){
               w = p->actualWidth[i];
            }else{
               w = 10;
            }
            fprintf(p->out,"%-*.*s%s",w,w,"-----------------------------------"
                   "----------------------------------------------------------",
                    i==nArg-1 ? "\n": "  ");
          }
        }
      }
      for(i=0; i<nArg; i++){
        int w;
        if( i<ArraySize(p->actualWidth) ){
           w = p->actualWidth[i];
        }else{
           w = 10;
        }
        fprintf(p->out,"%-*.*s%s",w,w,
            azArg[i] ? azArg[i] : "", i==nArg-1 ? "\n": "  ");
      }
      break;
    }
    case MODE_Semi:
    case MODE_List: {
      if( p->cnt++==0 && p->showHeader ){
        for(i=0; i<nArg; i++){
          fprintf(p->out,"%s%s",azCol[i], i==nArg-1 ? "\n" : p->separator);
        }
      }
      for(i=0; i<nArg; i++){
        char *z = azArg[i];
        if( z==0 ) z = "";
        while( *z ){
          int j;
          for(j=0; z[j] && z[j]!=p->escape && z[j]!='\\'; j++){}
          if( j>0 ){
            fprintf(p->out, "%.*s", j, z);
          }
          if( z[j] ){
            fprintf(p->out, "\\%c", z[j]);
            z++;
          }
          z += j;
        }
        if( i<nArg-1 ){
          fprintf(p->out, "%s", p->separator);
        }else if( p->mode==MODE_Semi ){
          fprintf(p->out, ";\n");
        }else{
          fprintf(p->out, "\n");
        }
      }
      break;
    }
    case MODE_Html: {
      if( p->cnt++==0 && p->showHeader ){
        fprintf(p->out,"<TR>");
        for(i=0; i<nArg; i++){
          fprintf(p->out,"<TH>%s</TH>",azCol[i]);
        }
        fprintf(p->out,"</TR>\n");
      }
      fprintf(p->out,"<TR>");
      for(i=0; i<nArg; i++){
        fprintf(p->out,"<TD>");
        output_html_string(p->out, azArg[i] ? azArg[i] : "");
        fprintf(p->out,"</TD>\n");
      }
      fprintf(p->out,"</TD></TR>\n");
      break;
    }
    case MODE_Insert: {
      fprintf(p->out,"INSERT INTO '%s' VALUES(",p->zDestTable);
      for(i=0; i<nArg; i++){
        char *zSep = i>0 ? ",": "";
        if( azArg[i]==0 ){
          fprintf(p->out,"%sNULL",zSep);
        }else if( is_numeric(azArg[i]) ){
          fprintf(p->out,"%s%s",zSep, azArg[i]);
        }else{
          if( zSep[0] ) fprintf(p->out,"%s",zSep);
          output_quoted_string(p->out, azArg[i]);
        }
      }
      fprintf(p->out,");\n");
    }
  }      
  return 0;
}

/*
** This is a different callback routine used for dumping the database.
** Each row received by this callback consists of a table name,
** the table type ("index" or "table") and SQL to create the table.
** This routine should print text sufficient to recreate the table.
*/
static int dump_callback(void *pArg, int nArg, char **azArg, char **azCol){
  struct callback_data *pData = (struct callback_data *)pArg;
  if( nArg!=3 ) return 1;
  fprintf(pData->out, "%s;\n", azArg[2]);
  if( strcmp(azArg[1],"table")==0 ){
    struct callback_data d2;
    char zSql[1000];
    d2 = *pData;
    d2.mode = MODE_List;
    d2.escape = '\t';
    strcpy(d2.separator,"\t");
    fprintf(pData->out, "COPY '%s' FROM STDIN;\n", azArg[0]);
    sprintf(zSql, "SELECT * FROM '%s'", azArg[0]);
    sqlite_exec(pData->db, zSql, callback, &d2, 0);
    fprintf(pData->out, "\\.\n");
  }
  fprintf(pData->out, "VACUUM '%s';\n", azArg[0]);
  return 0;
}

/*
** Text of a help message
*/
static char zHelp[] = 
  ".dump ?TABLE? ...      Dump the database in an text format\n"
  ".exit                  Exit this program\n"
  ".explain               Set output mode suitable for EXPLAIN\n"
  ".header ON|OFF         Turn display of headers on or off\n"
  ".help                  Show this message\n"
  ".indices TABLE         Show names of all indices on TABLE\n"
  ".mode MODE             Set mode to one of \"line\", \"column\", \n"
  "                       \"insert\", \"list\", or \"html\"\n"
  ".mode insert TABLE     Generate SQL insert statements for TABLE\n"
  ".output FILENAME       Send output to FILENAME\n"
  ".output stdout         Send output to the screen\n"
  ".schema ?TABLE?        Show the CREATE statements\n"
  ".separator STRING      Change separator string for \"list\" mode\n"
  ".tables ?PATTERN?      List names of tables matching a pattern\n"
  ".timeout MS            Try opening locked tables for MS milliseconds\n"
  ".width NUM NUM ...     Set column widths for \"column\" mode\n"
;

/*
** If an input line begins with "." then invoke this routine to
** process that line.
*/
static void do_meta_command(char *zLine, sqlite *db, struct callback_data *p){
  int i = 1;
  int nArg = 0;
  int n, c;
  char *azArg[50];

  /* Parse the input line into tokens.
  */
  while( zLine[i] && nArg<ArraySize(azArg) ){
    while( isspace(zLine[i]) ){ i++; }
    if( zLine[i]=='\'' || zLine[i]=='"' ){
      int delim = zLine[i++];
      azArg[nArg++] = &zLine[i];
      while( zLine[i] && zLine[i]!=delim ){ i++; }
      if( zLine[i]==delim ){
        zLine[i++] = 0;
      }
    }else{
      azArg[nArg++] = &zLine[i];
      while( zLine[i] && !isspace(zLine[i]) ){ i++; }
      if( zLine[i] ) zLine[i++] = 0;
    }
  }

  /* Process the input line.
  */
  if( nArg==0 ) return;
  n = strlen(azArg[0]);
  c = azArg[0][0];
 
  if( c=='d' && strncmp(azArg[0], "dump", n)==0 ){
    char *zErrMsg = 0;
    char zSql[1000];
    if( nArg==1 ){
      sprintf(zSql, "SELECT name, type, sql FROM sqlite_master "
                    "WHERE type!='meta' "
                    "ORDER BY tbl_name, type DESC, name");
      sqlite_exec(db, zSql, dump_callback, p, &zErrMsg);
    }else{
      int i;
      for(i=1; i<nArg && zErrMsg==0; i++){
        sprintf(zSql, "SELECT name, type, sql FROM sqlite_master "
                      "WHERE tbl_name LIKE '%.800s' AND type!='meta' "
                      "ORDER BY type DESC, name", azArg[i]);
        sqlite_exec(db, zSql, dump_callback, p, &zErrMsg);
        
      }
    }
    if( zErrMsg ){
      fprintf(stderr,"Error: %s\n", zErrMsg);
      free(zErrMsg);
    }
  }else

  if( c=='e' && strncmp(azArg[0], "exit", n)==0 ){
    exit(0);
  }else

  if( c=='e' && strncmp(azArg[0], "explain", n)==0 ){
    p->mode = MODE_Column;
    p->showHeader = 1;
    p->colWidth[0] = 4;
    p->colWidth[1] = 12;
    p->colWidth[2] = 5;
    p->colWidth[3] = 5;
    p->colWidth[4] = 40;
  }else

  if( c=='h' && strncmp(azArg[0], "header", n)==0 && nArg>1 ){
    int j;
    char *z = azArg[1];
    int val = atoi(azArg[1]);
    for(j=0; z[j]; j++){
      if( isupper(z[j]) ) z[j] = tolower(z[j]);
    }
    if( strcmp(z,"on")==0 ){
      val = 1;
    }else if( strcmp(z,"yes")==0 ){
      val = 1;
    } 
    p->showHeader = val;
  }else

  if( c=='h' && strncmp(azArg[0], "help", n)==0 ){
    fprintf(stderr,zHelp);
  }else

  if( c=='i' && strncmp(azArg[0], "indices", n)==0 && nArg>1 ){
    struct callback_data data;
    char *zErrMsg = 0;
    char zSql[1000];
    memcpy(&data, p, sizeof(data));
    data.showHeader = 0;
    data.mode = MODE_List;
    sprintf(zSql, "SELECT name FROM sqlite_master "
                  "WHERE type='index' AND tbl_name LIKE '%.800s' "
                  "ORDER BY name", azArg[1]);
    sqlite_exec(db, zSql, callback, &data, &zErrMsg);
    if( zErrMsg ){
      fprintf(stderr,"Error: %s\n", zErrMsg);
      free(zErrMsg);
    }
  }else

  if( c=='m' && strncmp(azArg[0], "mode", n)==0 && nArg>=2 ){
    int n2 = strlen(azArg[1]);
    if( strncmp(azArg[1],"line",n2)==0 ){
      p->mode = MODE_Line;
    }else if( strncmp(azArg[1],"column",n2)==0 ){
      p->mode = MODE_Column;
    }else if( strncmp(azArg[1],"list",n2)==0 ){
      p->mode = MODE_List;
    }else if( strncmp(azArg[1],"html",n2)==0 ){
      p->mode = MODE_Html;
    }else if( strncmp(azArg[1],"insert",n2)==0 ){
      p->mode = MODE_Insert;
      if( nArg>=3 ){
        sprintf(p->zDestTable,"%.*s", (int)(sizeof(p->zDestTable)-1), azArg[2]);
      }else{
        sprintf(p->zDestTable,"table");
      }
    }
  }else

  if( c=='o' && strncmp(azArg[0], "output", n)==0 && nArg==2 ){
    if( p->out!=stdout ){
      fclose(p->out);
    }
    if( strcmp(azArg[1],"stdout")==0 ){
      p->out = stdout;
    }else{
      p->out = fopen(azArg[1], "w");
      if( p->out==0 ){
        fprintf(stderr,"can't write to \"%s\"\n", azArg[1]);
        p->out = stdout;
      }
    }
  }else

  if( c=='s' && strncmp(azArg[0], "schema", n)==0 ){
    struct callback_data data;
    char *zErrMsg = 0;
    char zSql[1000];
    memcpy(&data, p, sizeof(data));
    data.showHeader = 0;
    data.mode = MODE_Semi;
    if( nArg>1 ){
      sprintf(zSql, "SELECT sql FROM sqlite_master "
                    "WHERE tbl_name LIKE '%.800s' AND type!='meta'"
                    "ORDER BY type DESC, name",
         azArg[1]);
    }else{
      sprintf(zSql, "SELECT sql FROM sqlite_master "
         "WHERE type!='meta' "
         "ORDER BY tbl_name, type DESC, name");
    }
    sqlite_exec(db, zSql, callback, &data, &zErrMsg);
    if( zErrMsg ){
      fprintf(stderr,"Error: %s\n", zErrMsg);
      free(zErrMsg);
    }
  }else

  if( c=='s' && strncmp(azArg[0], "separator", n)==0 && nArg==2 ){
    sprintf(p->separator, "%.*s", (int)ArraySize(p->separator)-1, azArg[1]);
  }else

  if( c=='t' && n>1 && strncmp(azArg[0], "tables", n)==0 ){
    char **azResult;
    int nRow, rc;
    char *zErrMsg;
    char zSql[1000];
    if( nArg==1 ){
      sprintf(zSql,
        "SELECT name FROM sqlite_master "
        "WHERE type='table' "
        "ORDER BY name");
    }else{
      sprintf(zSql,
        "SELECT name FROM sqlite_master "
        "WHERE type='table' AND name LIKE '%%%.100s%%' "
        "ORDER BY name", azArg[1]);
    }
    rc = sqlite_get_table(db, zSql, &azResult, &nRow, 0, &zErrMsg);
    if( zErrMsg ){
      fprintf(stderr,"Error: %s\n", zErrMsg);
      free(zErrMsg);
    }
    if( rc==SQLITE_OK ){
      int len, maxlen = 0;
      int i, j;
      int nPrintCol, nPrintRow;
      for(i=1; i<=nRow; i++){
        if( azResult[i]==0 ) continue;
        len = strlen(azResult[i]);
        if( len>maxlen ) maxlen = len;
      }
      nPrintCol = 80/(maxlen+2);
      if( nPrintCol<1 ) nPrintCol = 1;
      nPrintRow = (nRow + nPrintCol - 1)/nPrintCol;
      for(i=0; i<nPrintRow; i++){
        for(j=i+1; j<=nRow; j+=nPrintRow){
          char *zSp = j<=nPrintRow ? "" : "  ";
          printf("%s%-*s", zSp, maxlen, azResult[j] ? azResult[j] : "");
        }
        printf("\n");
      }
    }
    sqlite_free_table(azResult);
  }else

  if( c=='t' && n>1 && strncmp(azArg[0], "timeout", n)==0 && nArg>=2 ){
    sqlite_busy_timeout(db, atoi(azArg[1]));
  }else

  if( c=='w' && strncmp(azArg[0], "width", n)==0 ){
    int j;
    for(j=1; j<nArg && j<ArraySize(p->colWidth); j++){
      p->colWidth[j-1] = atoi(azArg[j]);
    }
  }else

  {
    fprintf(stderr, "unknown command: \"%s\". Enter \".help\" for help\n",
      azArg[0]);
  }
}

int main(int argc, char **argv){
  sqlite *db;
  char *zErrMsg = 0;
  char *argv0 = argv[0];
  struct callback_data data;

  memset(&data, 0, sizeof(data));
  data.mode = MODE_List;
  strcpy(data.separator,"|");
  data.showHeader = 0;
  while( argc>=2 && argv[1][0]=='-' ){
    if( strcmp(argv[1],"-html")==0 ){
      data.mode = MODE_Html;
      argc--;
      argv++;
    }else if( strcmp(argv[1],"-list")==0 ){
      data.mode = MODE_List;
      argc--;
      argv++;
    }else if( strcmp(argv[1],"-line")==0 ){
      data.mode = MODE_Line;
      argc--;
      argv++;
    }else if( argc>=3 && strcmp(argv[0],"-separator")==0 ){
      sprintf(data.separator,"%.*s",(int)sizeof(data.separator)-1,argv[2]);
      argc -= 2;
      argv += 2;
    }else if( strcmp(argv[1],"-header")==0 ){
      data.showHeader = 1;
      argc--;
      argv++;
    }else if( strcmp(argv[1],"-noheader")==0 ){
      data.showHeader = 0;
      argc--;
      argv++;
    }else{
      fprintf(stderr,"%s: unknown option: %s\n", argv0, argv[1]);
      return 1;
    }
  }
  if( argc!=2 && argc!=3 ){
    fprintf(stderr,"Usage: %s ?OPTIONS? FILENAME ?SQL?\n", argv0);
    exit(1);
  }
  data.db = db = sqlite_open(argv[1], 0666, &zErrMsg);
  if( db==0 ){
    data.db = db = sqlite_open(argv[1], 0444, &zErrMsg);
    if( db==0 ){
      if( zErrMsg ){
        fprintf(stderr,"Unable to open database \"%s\": %s\n", argv[1],zErrMsg);
      }else{
        fprintf(stderr,"Unable to open database %s\n", argv[1]);
      }
      exit(1);
    }else{
      fprintf(stderr,"Database \"%s\" opened READ ONLY!\n", argv[1]);
    }
  }
  data.out = stdout;
  if( argc==3 ){
    if( sqlite_exec(db, argv[2], callback, &data, &zErrMsg)!=0 && zErrMsg!=0 ){
      fprintf(stderr,"SQL error: %s\n", zErrMsg);
      exit(1);
    }
  }else{
    char *zLine;
    char *zSql = 0;
    int nSql = 0;
    int istty = isatty(0);
    if( istty ){
      printf(
        "SQLite version %s\n"
        "Enter \".help\" for instructions\n",
        sqlite_version
      );
    }
    while( (zLine = one_input_line(zSql, istty))!=0 ){
      if( zLine && zLine[0]=='.' ){
        do_meta_command(zLine, db, &data);
        free(zLine);
        continue;
      }
      if( zSql==0 ){
        nSql = strlen(zLine);
        zSql = malloc( nSql+1 );
        strcpy(zSql, zLine);
      }else{
        int len = strlen(zLine);
        zSql = realloc( zSql, nSql + len + 2 );
        if( zSql==0 ){
          fprintf(stderr,"%s: out of memory!\n", argv0);
          exit(1);
        }
        strcpy(&zSql[nSql++], "\n");
        strcpy(&zSql[nSql], zLine);
        nSql += len;
      }
      free(zLine);
      if( sqlite_complete(zSql) ){
        data.cnt = 0;
        if( sqlite_exec(db, zSql, callback, &data, &zErrMsg)!=0 
             && zErrMsg!=0 ){
          printf("SQL error: %s\n", zErrMsg);
          free(zErrMsg);
          zErrMsg = 0;
        }
        free(zSql);
        zSql = 0;
        nSql = 0;
      }
    }
  }
  sqlite_close(db);
  return 0;
}