taichino.com

#import "FMDatabase.h"
#import "FMDatabaseAdditions.h"
#define DBFILE     @"fmdb_test.db"
 
// データベースインスタンスを返す
- (FMDatabase*)_getDB:(NSString*)dbName {
	NSArray*  pathArray = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
	NSString* docdir = [pathArray objectAtIndex:0];
	NSString* dbpath = [docdir stringByAppendingPathComponent:dbName];
	FMDatabase* db = [FMDatabase databaseWithPath:dbpath];
    if (![db open]) {
        @throw [NSException exceptionWithName:@"DBOpenException" reason:@"couldn't open specified db file" userInfo:nil];
    }
 
    return db;
}
 
// テーブル作成
- (IBAction)createTable {
    FMDatabase* db = [self _getDB:DBFILE];
    NSDictionary* tables = [NSDictionary dictionaryWithObjectsAndKeys:
        @"CREATE TABLE authors(id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT)",
        @"authors",
        @"CREATE TABLE books(id INTEGER PRIMARY KEY AUTOINCREMENT, title TEXT, author_id INTEGER, score INTEGER)",
        @"books",
        nil
    ];
 
    for (NSString* tableName in tables) {
        if (![db tableExists:tableName]) {
            if (![db executeUpdate:[tables objectForKey:tableName], nil]) {
                NSLog(@"ERROR: %d: %@", [db lastErrorCode], [db lastErrorMessage]);
            }
        }
    }
 
    // table already exists error を起こしてみる
    for (NSString* tableName in tables) { 
        if (![db executeUpdate:[tables objectForKey:tableName], nil]) {
            NSLog(@"ERROR: %d: %@", [db lastErrorCode], [db lastErrorMessage]); // error codeは1
        }
    }
 
    [db close];
}
 
// レコードの挿入
- (IBAction)insert {
    FMDatabase* db = [self _getDB:DBFILE];
 
    NSArray* fixture = [NSArray arrayWithObjects:
                             [NSDictionary dictionaryWithObjectsAndKeys:
                                           @"村上春樹", @"author",
                                           [NSNumber numberWithInt:1], @"id",
                                           [NSArray arrayWithObjects:@"１Ｑ８４", @"ねじまき鳥クロニクル", nil],
                                           @"books",
                                           nil
                             ],
                             [NSDictionary dictionaryWithObjectsAndKeys:
                                           @"ポールグレアム", @"author",
                                           [NSNumber numberWithInt:2], @"id",
                                           [NSArray arrayWithObjects:@"ハッカーと画家", @"On Lisp", nil],
                                           @"books",
                                           nil
                             ],
                             nil
        ];
 
    for (NSDictionary* item in fixture) {
        NSNumber* author_id = [item objectForKey:@"id"];
        NSString* author    = [item objectForKey:@"author"];
        NSArray*  books     = [item objectForKey:@"books"];
        if ([db executeUpdate:@"INSERT INTO authors(id, name) VALUES (?, ?)" , author_id, author]) {
            for (NSString* book in books) {
                // its too ugly, COUNT(*) as cnt should be used in SQL
                FMResultSet* rs = [db executeQuery:@"SELECT COUNT(*) FROM books WHERE author_id = ? and title = ?", author_id, book];
                if ([rs next] && [rs intForColumn:@"COUNT(*)"] == 0) {
                    [db executeUpdate:@"INSERT INTO books(title, author_id) VALUES (?, ?)" , book, author_id];
                }
                [rs close];
            }
        }
        else {
            // if duplicated, error code 19 will return (Constraint Error)
            NSLog(@"ERROR: %d: %@", [db lastErrorCode], [db lastErrorMessage]);
        }
    }
 
    [db close];
}
 
// レコードの取得
- (IBAction)select {
    FMDatabase* db = [self _getDB:DBFILE];
    FMResultSet* rs = [db executeQuery:@"SELECT * FROM authors, books WHERE authors.id = books.author_id"];
    while ([rs next]) {
        NSLog(@"%d %@ %d ",
              [rs intForColumn:@"id"],
              [rs stringForColumn:@"title"],
              [rs intForColumn:@"score"]);
    }
    [rs close];
    [db close];
}
 
// レコードの更新
- (IBAction)update {
    FMDatabase* db = [self _getDB:DBFILE];
    if (![db executeUpdate:@"UPDATE books SET score = 5 WHERE title = ?", @"１Ｑ８４"]) {
        NSLog(@"ERROR: %d: %@", [db lastErrorCode], [db lastErrorMessage]);
    }
    if (![db executeUpdate:@"UPDATE books SET score = 4 WHERE title = ?", @"ハッカーと画家"]) {
        NSLog(@"ERROR: %d: %@", [db lastErrorCode], [db lastErrorMessage]);
    }
    [db close];
}
 
// レコードの削除
- (IBAction)delete {
    FMDatabase* db = [self _getDB:DBFILE];
 
    NSArray* tables = [NSArray arrayWithObjects:@"authors", @"books", nil];
    for (NSString* table in tables) {
        if (![db executeUpdate:[NSString stringWithFormat:@"DELETE FROM %s", [table cStringUsingEncoding:NSUTF8StringEncoding]]]) {
            NSLog(@"ERROR: %d: %@", [db lastErrorCode], [db lastErrorMessage]);
        }
    }
    [db close];
}