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Sqlite3_open: "cannot open database file"

I get "unable to open database file" when I execute rc = sqlite3_open ("test.db", & db); ??

sqlite3 *db; // sqlite3 db struct
char *zErrMsg = 0;
int rc;

// Open the test.db file
rc = sqlite3_open("test.db", &db); // <-- creates DB if not found ??

if( rc ){
    // failed
    fprintf(stderr, "ERROR: Can't open database: %s\n", sqlite3_errmsg(db));
}
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2 answers


sqlite3_open

returns an error if the database does not already exist. To create a database if it doesn't already exist, use sqlite3_open_v2

with flags SQLITE_OPEN_CREATE

and SQLITE_OPEN_READWRITE

( both are required ):

rc = sqlite3_open_v2(/* DB Path */, &db, SQLITE_OPEN_CREATE | SQLITE_OPEN_READWRITE, NULL);

Link



To find /* DB PATH */

, you need to specify the filename in the document directory:

- (NSString *) applicationDocumentsDirectory 
{    
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *basePath = ([paths count] > 0) ? [paths objectAtIndex:0] : nil;
    return basePath;
}

This convenience method can be used to concatenate the document path with the database name:

NSString *documents = [self applicationDocumentsDirectory];
NSString *dbPath = [documents stringByAppendingPathComponent:@"test.db"];

rc = sqlite3_open_v2([dbPath UTF8String], &db, SQLITE_OPEN_CREATE | SQLITE_OPEN_READWRITE, NULL);
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#define SQLITE_OK 0
sqlite3 *db;
char *zErrMsg=0;
if(sqlite3_open("demo.db", &db) == SQLITE_OK)
{
    if(sqlite3_exec(db, "select * from Users", callback, 0, &zErrMsg) == SQLITE_OK)
            msgbox1("success");
    sqlite3_close(db);
}
else
    msgbox1("failure");


here is the sample code i am using;

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