0

データベースからレコードを削除したいのですが、

file.h でデータベースを定義し、file.m で挿入データと読み取りデータを定義しますが、削除は機能しませんでした。

これはファイルです.h

#import "sqlite3.h"
#define DATA_FILE @"prova12"
#define TABLE_NAME @"password"
#define FIELDS_NAME_SID @"pass"
#define FIELDS_NAME_SNAME @"foto"
#define FIELDS_NAME_SCLASS @"studentClass"
#define FIELDS_NAME_PROVA @"provaClass"

{sqlite3 *db;
}

ファイル内.m

パスの場合:

    -(NSString *)dataFilePath {
    NSArray * myPaths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory,NSUserDomainMask, YES); NSString * myDocPath = [myPaths objectAtIndex:0];
    NSString *filename = [myDocPath stringByAppendingPathComponent:DATA_FILE];
    return filename;

読み取り用:

   -(NSMutableArray*)selectAll
  {
NSMutableArray *list = [[NSMutableArray alloc] initWithObjects:nil];
NSString *filename = [self dataFilePath];
NSLog(@"%@",filename);
if (sqlite3_open([filename UTF8String], &db) != SQLITE_OK) {
    sqlite3_close(db);
    NSAssert(NO,@"no");
} else {

    NSString *qsql = [NSString stringWithFormat: @"SELECT %@ FROM %@", FIELDS_NAME_SID, TABLE_NAME];
    NSLog(@"qui%@",qsql);
    sqlite3_stmt *statement;

    if (sqlite3_prepare_v2(db, [qsql UTF8String], -1, &statement, NULL) == SQLITE_OK) {

        sqlite3_bind_text(statement, 1, [inserisci.text UTF8String], -1, NULL);


        while (sqlite3_step(statement) == SQLITE_ROW) {
            char *field1 = (char *) sqlite3_column_text(statement, 0);
            NSString *field1Str = [[NSString alloc] initWithUTF8String: field1];
            //studentId.text = field1Str;
            //[field1Str release];
            [list addObject:field1Str];
            NSLog(@"%d",list.count);

        }
    }

    sqlite3_finalize(statement);
    sqlite3_close(db);

}
return list;
}

これは保存用です：

-(IBAction) save {
NSString *filename = [self dataFilePath];


if (sqlite3_open([filename UTF8String], &db) != SQLITE_OK) {
    sqlite3_close(db);
    NSAssert(NO,@"no");
} else {

    NSString *sqlStr = [NSString stringWithFormat: @"INSERT OR REPLACE INTO %@ (%@, %@, %@ ,%@) VALUES (?,?,?,?)",
                        TABLE_NAME, FIELDS_NAME_SID, FIELDS_NAME_SNAME, FIELDS_NAME_SCLASS, FIELDS_NAME_PROVA];

    sqlite3_stmt *statement;

    if (sqlite3_prepare_v2(db, [sqlStr UTF8String], -1, &statement, NULL) == SQLITE_OK) {

        NSLog(@"quiiiiddddd %@", filename);
        sqlite3_bind_text(statement, 1, [inserisci.text UTF8String], -1, NULL);
        sqlite3_bind_text(statement, 2, [immagine       UTF8String], -1, NULL);
        sqlite3_bind_text(statement, 3, [inserisci.text UTF8String], -1, NULL);
        sqlite3_bind_text(statement, 4, [inserisci.text UTF8String], -1, NULL);



        if (sqlite3_step(statement) != SQLITE_DONE) {
            NSAssert(0, @"no");
        }
    }

    sqlite3_finalize(statement);
    sqlite3_close(db);

}

しかし、データを削除する考えがありません。誰か助けてもらえますか?

4

2 に答える 2

1

選択したすべてのレコードまたは鉱石を削除したい

-(bool)deleteEvent:(int)eventID
{
    DBSettings *dbSettings = [[DBSettings alloc]init];
    [dbSettings checkAndCreateDatabase];
    DatabaseName=dbSettings.DBName;
    DatabasePath=dbSettings.DBPath;
    [dbSettings release];

    sqlite3 *database;
    if(sqlite3_open([DatabasePath UTF8String], &database) == SQLITE_OK)
    {
        const char *sqlStatement;
        NSString *query = [NSString stringWithFormat:@"%@'%i'",kDeleteQuery,eventID];

        //Convert NSString to char pointer for execution
        sqlStatement=[query UTF8String];

        if(sqlite3_prepare_v2(database, sqlStatement, -1, &deleteStmt, NULL) != SQLITE_OK)
            NSAssert1(0, @"Error while creating add statement. '%s'", sqlite3_errmsg(database));

        if(SQLITE_DONE != sqlite3_step(deleteStmt))
        {
            NSAssert1(0, @"Error while deleting data. '%s'", sqlite3_errmsg(database));
        }

        sqlite3_finalize(deleteStmt);
        sqlite3_close(database);
        return YES;
}

return NO;

}

kDeleteQuery "クエリはすべてのレコードまたは選択されています"

于 2013-06-24T07:47:29.720 に答える