Question

我有一个sqlite文件，我添加到我的Xcode项目并将其复制到iPhone上的Documents目录中。我已经验证它存在，但似乎仍然无法更新文件。下面的代码是应该将数据传递到sqlite文件的操作方法：

-(IBAction)saveButtonPressed:(id)sender
{
    //Catch current time in specified format
    NSDateFormatter *dateFormat = [[NSDateFormatter alloc]init];
    [dateFormat setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
    NSDate *currentDate = [NSDate date];
    NSString *localDateString = [dateFormat stringFromDate:currentDate];

    //Catch location
    CLLocation *location = [self.locationManager location];
    CLLocationCoordinate2D coordinate = [location coordinate];
    NSString *currentCoordinate = [NSString stringWithFormat:@"%f, %f",coordinate.latitude,coordinate.longitude];
    NSLog(@"%@ ... %@",localDateString,currentCoordinate);


    NSString *query = [NSString stringWithFormat:@"INSERT INTO sqliteData values(null, 'near', '%@', '%@')", localDateString, currentCoordinate];

    [self.dbManager executeQuery:query];

    if (self.dbManager.affectedRows != 0) {
        NSLog(@"Query was executed");

    }
    else{
        NSLog(@"Could not execute query.");
    }
}

executeQuery方法：

- (void)executeQuery:(NSString *)query
{
    [self runQuery:[query UTF8String] isQueryExecutable:YES];
}

编辑： runQuery方法

-(void)runQuery:(const char *)query isQueryExecutable:(BOOL)queryExecutable{
    sqlite3 *sqlite3Database;

    // Define database file path.
    NSString *databasePath = [self.documentsDirectory stringByAppendingPathComponent:self.databaseFilename];

    // Initialize the results array.
    if (self.arrayResults != nil) {
        [self.arrayResults removeAllObjects];
        self.arrayResults = nil;
    }
    self.arrayResults = [[NSMutableArray alloc] init];

    // Initialize the column names array.
    if (self.arrColumnNames != nil) {
        [self.arrColumnNames removeAllObjects];
        self.arrColumnNames = nil;
    }
    self.arrColumnNames = [[NSMutableArray alloc] init];


    // Open the database.
    BOOL openDatabaseResult = sqlite3_open([databasePath UTF8String], &sqlite3Database);
    if(openDatabaseResult == SQLITE_OK) {
        // Declare a sqlite3_stmt object in which will be stored the query after having been compiled into a SQLite statement.
        sqlite3_stmt *compiledStatement;

        // Load all data from database to memory.
        BOOL prepareStatementResult = sqlite3_prepare_v2(sqlite3Database, query, -1, &compiledStatement, NULL);
        if(prepareStatementResult == SQLITE_OK) {
            // Check if the query is non-executable.
            if (!queryExecutable){
                // In this case data must be loaded from the database.

                // Declare an array to keep the data for each fetched row.
                NSMutableArray *arrDataRow;

                // Loop through the results and add them to the results array row by row.
                while(sqlite3_step(compiledStatement) == SQLITE_ROW) {
                    // Initialize the mutable array that will contain the data of a fetched row.
                    arrDataRow = [[NSMutableArray alloc] init];

                    // Get the total number of columns.
                    int totalColumns = sqlite3_column_count(compiledStatement);

                    // Go through all columns and fetch each column data.
                    for (int i=0; i<totalColumns; i++){
                        // Convert the column data to text (characters).
                        char *dbDataAsChars = (char *)sqlite3_column_text(compiledStatement, i);

                        // If there are contents in the currenct column (field) then add them to the current row array.
                        if (dbDataAsChars != NULL) {
                            // Convert the characters to string.
                            [arrDataRow addObject:[NSString  stringWithUTF8String:dbDataAsChars]];
                        }

                        // Keep the current column name.
                        if (self.arrColumnNames.count != totalColumns) {
                            dbDataAsChars = (char *)sqlite3_column_name(compiledStatement, i);
                            [self.arrColumnNames addObject:[NSString stringWithUTF8String:dbDataAsChars]];
                        }
                    }

                    // Store each fetched data row in the results array, but first check if there is actually data.
                    if (arrDataRow.count > 0) {
                        [self.arrayResults addObject:arrDataRow];
                    }
                }
            }
            else {
                int executeQueryResults = sqlite3_step(compiledStatement);
                if (executeQueryResults == SQLITE_DONE) {
                    // Keep the affected rows.
                    self.affectedRows = sqlite3_changes(sqlite3Database);

                    // Keep the last inserted row ID.
                    self.lastInsertedRowID = sqlite3_last_insert_rowid(sqlite3Database);
                }
                else {
                    NSLog(@"DB Error: %s", sqlite3_errmsg(sqlite3Database));
                }
            }
        }
        else {
            NSLog(@"%s", sqlite3_errmsg(sqlite3Database));
        }
        sqlite3_finalize(compiledStatement);

    }
    sqlite3_close(sqlite3Database);
}

Answer 1

问题最终导致我的设备上有一个旧的SQLite文件副本。我删除了应用程序并重新启动它;这就是诀窍。

更新不反映iOS中的SQLite文件

1 个答案: