SQLite with Ansi C and xCode -


i'm starting bottom-up learn ipad development after 15 years cold fusion. i'm getting comfortable ansi c , xcode, stumped taking next step sqlite.

i've built database (airports.sqlite) razorsql , installed in same directory main.c i've installed amalgamated sqlite3.h , sqlite3.h files.

everything compiles ok, following message when run...

error in select statement select length runways order length desc limit 5 [no such table: runways].

the database has runways table in it. can set me straight? here's code:

#include <stdio.h> #include <stdlib.h> #include <string.h> #include "sqlite3.h" #include "weightbalance.h"  sqlite3* db; int first_row;  int select_callback(void *p_data, int num_fields, char **p_fields, char **p_col_names) {      int i;     int *p_rn = (int*)p_data;      if (first_row) {         first_row = 0;          for(i=0; < num_fields; i++) {             printf("%20s", p_col_names[i]);         }         printf("\n");         for(i=0; i< num_fields*20; i++) {             printf("=");         }         printf("\n");     }      (*p_rn)++;      for(i=0; < num_fields; i++) {         printf("%20s", p_fields[i]);     }      printf("\n");     return 0; }   void select_stmt(const char* stmt) {     char *errmsg;     int   ret;     int   nrecs = 0;      first_row = 1;      ret = sqlite3_exec(db, stmt, select_callback, &nrecs, &errmsg);      if(ret!=sqlite_ok) {         printf("error in select statement %s [%s].\n", stmt, errmsg);     }     else {         printf("\n   %d records returned.\n", nrecs);     } }  void sql_stmt(const char* stmt) {     char *errmsg;     int   ret;      ret = sqlite3_exec(db, stmt, 0, 0, &errmsg);      if(ret != sqlite_ok) {         printf("error in statement: %s [%s].\n", stmt, errmsg);     } }  int main() {     sqlite3_open("airports.sqlite", &db);      if(db == 0) {         printf("could not open database.");         return 1;     }      printf("\nselecting airports longest runways.\n\n");     select_stmt("select length runways order length desc limit 5");      sqlite3_close(db);     return 0; }

most likely, file "airports.sqlite" opened in main() not 1 think is. without path information, sqlite3_open() open file in current working directory.

as debug step, add "printf(getwd(null))" before sqlite3_open() statement. you'll know whether you're opening existing database or creating new, empty 1 missing table.

also, since you're using xcode, can pass path database command-line parameter (argv). in xcode 4, choose product->edit scheme. in "run" section, add path "arguments pass on launch". can pass argv[1] sqlite3_open().


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