Prepare-error : no such table: items - iphone

Question

this function is showing me the error that "Prepare-error #0: no such table: items
". can some one please help me out in resolving this error.
- (void)viewDidLoad
{
[super viewDidLoad];
const char *dbpath = [databasePath UTF8String];
sqlite3_stmt *statement;
if (sqlite3_open(dbpath, &contactDB)== SQLITE_OK)
{
NSString *querySQL = [NSString stringWithFormat:#"Select name FROM items"];
const char *query_stmt = [querySQL UTF8String];
if (sqlite3_prepare_v2(contactDB, query_stmt, -1, &statement, NULL) == SQLITE_OK)
{ NSLog(#"Data not fetched");
if (sqlite3_step(statement) == SQLITE_ROW)
{NSLog(#"Prepare-error #%i: %s", (sqlite3_prepare_v2(contactDB, [querySQL UTF8String], -1, &statement, NULL) == SQLITE_OK), sqlite3_errmsg(contactDB));
NSString *namefeild = [[NSString alloc]initWithUTF8String:(const char *) sqlite3_column_text(statement, 0)];
[list objectAtIndex:namefeild];
}
else{
NSLog(#"Data not fetched");
}
sqlite3_finalize(statement);
}else {NSLog(#"Prepare-error #%i: %s", (sqlite3_prepare_v2(contactDB, query_stmt, -1, &statement, NULL) == SQLITE_OK), sqlite3_errmsg(contactDB));}
sqlite3_close(contactDB);
}
These two functions are n different viewcontrollers.
In view didload the database is created.
- (void)viewDidLoad
{
[super viewDidLoad];
NSString *docsDir;
NSArray *dirPath;
dirPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
docsDir = [dirPath objectAtIndex:0];
databasePath = [[NSString alloc]initWithString:[docsDir stringByAppendingPathComponent:#"contactDB"]];
NSFileManager *filemgr = [NSFileManager defaultManager];
if ([filemgr fileExistsAtPath: databasePath] == NO) {
const char *dbpath = [databasePath UTF8String];
if (sqlite3_open(dbpath, &contactDB) == SQLITE_OK) {
char *errMsg;
const char *sql_stmt = "create table if not exists items(name varchar, price integer, description varchar)";
if (sqlite3_exec(contactDB, sql_stmt, NULL, NULL, &errMsg) != SQLITE_OK)
{
NSLog(#"Fail to create table");
}
sqlite3_close(contactDB);
}else{
NSLog(#"Failed to open database");
}
}
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
and in save action the data is added to the database.
- (IBAction)save:(id)sender {
sqlite3_stmt *statement;
const char *dbpath = [ databasePath UTF8String];
if (sqlite3_open(dbpath, &contactDB) == SQLITE_OK) {
NSString *insertSQL = [NSString stringWithFormat:#"insert into items(name, price, description) values (\"%#\",\"%#\",\"%#\")", nametxt.text, pricetxt.text, description.text];
const char *insert_stmt = [insertSQL UTF8String];
sqlite3_prepare_v2(contactDB, insert_stmt, -1, &statement, NULL);
if (sqlite3_step(statement) == SQLITE_DONE)
{
NSLog(#"contact added");
nametxt.text= #"";
pricetxt.text = #"";
description.text = #"";
}else{
NSLog(#"Failed to add contact");
}
sqlite3_finalize(statement);
sqlite3_close(contactDB);
}
}

Answer 1

- (void)viewDidLoad
{
[super viewDidLoad];
const char *dbpath = [databasePath UTF8String];
NSLog("%#", databasePath);
...
...
}
Copy the database path to your clipboard and paste it into your console.
cd "[database path]"
sqlite3 database_filename.db
.dump
After the .dump command, do you see the creation statement for your table? If not, then you need to double check the location of where you are actually creating your database. It would actually be very helpful if you updated your answer with the contents of the .dump command.

Answer 2

Typically this means that the table does not exist in the database you opened. You should find the database in your simulator's Documents folder (~/Library/Application Support/iPhone Simulator) and, open it in your MacOS SQLite tool of choice, see for yourself whether the table is there. I suspect it will not be there.
A common source of this problem is for a file at the databasePath to not exist (e.g. you might have copy of database in the bundle, but not the Documents folder), in which case sqlite3_open will quietly create a new, blank database at databasePath.
Assuming you don't want it to create a blank database when it doesn't find it, you should:
Remove your app from the simulator/device (so that any blank databases are removed);
Check your original opening routine and use NSFileManager to check for the existence of the database if it's not already there (perhaps copying the database from the bundle to documents before continuing);
NSFileManager *fileManager = [NSFileManager defaultManager];
if (![fileManager fileExistsAtPath:databasePath]) {
NSString *bundlePath = [[NSBundle mainBundle] pathForResource:#"itemsdb" ofType:#"sqlite"];
[fileManager copyItemAtPath:bundlePath toPath:databasePath error:nil];
}
Or perhaps your code should dynamically create the table(s) if the database didn't exist, but the idea is the same. Check for existence of the file before opening it.
Perhaps in the future, consider using sqlite3_open_v2 with the SQLITE_OPEN_READWRITE option (but not the SQLITE_OPEN_CREATE option), which will not create the database for you and will report an error if the database was not found.
Having said the above (which is the general counsel when someone encounters an error like yours, where the table that you know "should" be there, isn't), there are specific issues unique to your code sample in the way you handle error reporting:
If step succeeds, you're reporting an error. Surely you meant to only do that if step failed.
The error you generate as a result of step says "prepare error". Surely that should be "step error".
Your logging of errors is calling the function that failed again in order to get the return code. You should save the return code when you first called the function, saving you from having to call it again for your error message. (This is important because sometimes the value returned by the function will change and reset your error message. Don't call the failed function again!) It's also more efficient to just save the original return code.
Thus:
if (sqlite3_open(dbpath, &contactDB)== SQLITE_OK)
{
NSString *querySQL = [NSString stringWithFormat:#"Select name FROM items"];
const char *query_stmt = [querySQL UTF8String];
int rc; // variable to hold the return code
if ((rc = sqlite3_prepare_v2(contactDB, query_stmt, -1, &statement, NULL)) == SQLITE_OK)
{
if ((rc = sqlite3_step(statement)) == SQLITE_ROW)
{
NSString *namefeild = [[NSString alloc]initWithUTF8String:(const char *) sqlite3_column_text(statement, 0)];
[list objectAtIndex:namefeild];
}
else {
if (rc == SQLITE_DONE)
NSLog(#"step found no data");
else
NSLog(#"step-error #%i: %s", rc, sqlite3_errmsg(contactDB));
}
sqlite3_finalize(statement);
} else {
NSLog(#"Prepare-error #%i: %s", rc, sqlite3_errmsg(contactDB));
}
sqlite3_close(contactDB);
}