编辑：解决了！在第一个密码框下方回答
当我尝试连接sqlite数据库（使用表TblTest）时。在我的应用程序的调试模式下，错误为：
*-[QueryClass getTestData：]中的断言失败，
*由于未捕获的异常“ NSInternalInconsistencyException”而终止应用程序，原因：“无法构建SQL来读取项目[没有此类表：TblTest]”
在发布模式（模拟器）下，它不会给出错误，但不会读取数据库。
该代码的行为就像可以连接到数据库，但无法读取TblTest吗？
我已经重置了模拟器并使用了清理和构建。
对不起，长代码：
@implementation QueryClass
@synthesize databaseName;
@synthesize databaseLite;
-(id)initWithDatabase:(NSString *)databaseNameP{
if(self = [super init]){
[self createEditableCopyOfDatabaseIfNeeded];
self.databaseName = databaseNameP;
self.databaseLite = [self getNewDBConnection];
}
return self;
}
- (void)createEditableCopyOfDatabaseIfNeeded {
NSLog(@"Creating editable copy of database");
// First, test for existence.
BOOL success;
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *writableDBPath = [documentsDirectory stringByAppendingPathComponent:self.databaseName];
success = [fileManager fileExistsAtPath:writableDBPath];
if (success) return;
// The writable database does not exist, so copy the default to the appropriate location.
NSString *defaultDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:self.databaseName];
success = [fileManager copyItemAtPath:defaultDBPath toPath:writableDBPath error:&error];
if (!success) {
NSAssert1(0, @"Failed to create writable database file with message ‘%@’.", [error localizedDescription]);
}
}
- (sqlite3 *) getNewDBConnection{
sqlite3 *newDBconnection;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:self.databaseName];
// Open the database. The database was prepared outside the application.
if (sqlite3_open([path UTF8String], &newDBconnection) == SQLITE_OK) {
NSLog(@"Database Successfully Opened ");
} else {
NSLog(@"Error in opening database ");
}
return newDBconnection;
}
-(NSMutableArray *)getTestData:(NSInteger) testId{
(NSMutableArray *testArray = [[NSMutableArray alloc]init];
int ret;
sqlite3_stmt *selStmt = nil;
const char *sql = "SELECT testId, name, FROM TblTest WHERE testId = ?";
if (!selStmt)
{ // build update statement
if (sqlite3_prepare_v2(self.databaseLite, sql, -1, &selStmt, NULL)!=SQLITE_OK)
{
selStmt = nil;
}
}
sqlite3_bind_int(selStmt, 1, testId);
if(!selStmt){
NSAssert1(0, @"Cant build SQL to read item [%s]", sqlite3_errmsg(self.databaseLite));
}
while ((ret=sqlite3_step(selStmt))==SQLITE_ROW)
{ // get the fields from the record set and assign to item
Test *test = [[Test alloc]init];
NSNumber *testId = [NSNumber numberWithInt: (int) sqlite3_column_int(selStmt, 0)];
NSString *name = [NSString stringWithUTF8String:(char *) sqlite3_column_text(selStmt, 1)];
test.testId =testId;
test.name =name;
[testArray addObject:pill];
[test release];
}
sqlite3_reset(selStmt);
return [testArray autorelease];
}
//in my function i do:
qc = [[QueryClass alloc]initWithDatabase:@"databaseLite.sql"];
[qc getTestData:0];
我使用this教程重写了代码，它的工作原理很吸引人。 :)
谢谢
-(id)initWithDatabase:(NSString *)databaseNameP{
if(self = [super init]){
[self createEditableCopyOfDatabaseIfNeeded];
[self initializeDatabase];
}
return self;
}
// Creates a writable copy of the bundled default database in the application Documents directory.
- (void)createEditableCopyOfDatabaseIfNeeded {
// First, test for existence.
BOOL success;
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *writableDBPath = [documentsDirectory stringByAppendingPathComponent:@"databaseLite4.sqlite"];
success = [fileManager fileExistsAtPath:writableDBPath];
if (success) return;
// The writable database does not exist, so copy the default to the appropriate location.
NSString *defaultDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"databaseLite4.sqlite"];
success = [fileManager copyItemAtPath:defaultDBPath toPath:writableDBPath error:&error];
if (!success) {
NSAssert1(0, @"Failed to create writable database file with message '%@'.", [error localizedDescription]);
}
}
// Open the database connection and retrieve minimal information for all objects.
- (void)initializeDatabase {
// The database is stored in the application bundle.
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
self.path = [documentsDirectory stringByAppendingPathComponent:@"databaseLite4.sqlite"];
}
最佳答案
解决自己的问题时，应提供解决方案作为答案，而不是更新问题。可以（在这种情况下建议）回答您自己的问题并将其接受为答案。您不会因为接受自己的答案而获得任何声誉，但是该问题将正确列出为已解决。
以下是我从您的问题中提取的答案。随时接受。
我使用this教程重写了代码，它的工作原理很吸引人。 :)
这是我的解决方案：
-(id)initWithDatabase:(NSString *)databaseNameP{
if(self = [super init]){
[self createEditableCopyOfDatabaseIfNeeded];
[self initializeDatabase];
}
return self;
}
// Creates a writable copy of the bundled default database in the application Documents directory.
- (void)createEditableCopyOfDatabaseIfNeeded {
// First, test for existence.
BOOL success;
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *writableDBPath = [documentsDirectory stringByAppendingPathComponent:@"databaseLite4.sqlite"];
success = [fileManager fileExistsAtPath:writableDBPath];
if (success) return;
// The writable database does not exist, so copy the default to the appropriate location.
NSString *defaultDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"databaseLite4.sqlite"];
success = [fileManager copyItemAtPath:defaultDBPath toPath:writableDBPath error:&error];
if (!success) {
NSAssert1(0, @"Failed to create writable database file with message '%@'.", [error localizedDescription]);
}
}
// Open the database connection and retrieve minimal information for all objects.
- (void)initializeDatabase {
// The database is stored in the application bundle.
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
self.path = [documentsDirectory stringByAppendingPathComponent:@"databaseLite4.sqlite"];
}
关于sql - SQLite表不存在，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/5950189/