如何从 SQLite 表中检索所有行? [英] How do I retrieve all the rows from an SQLite table?

问题描述

大家好，我正在 iphone 中执行一些数据库操作.. 请谁能解释我如何从表中检索所有行..在此示例中，它仅检索最新输入的数据..

hello guys i am doing some database operations in iphone .. please can anyone explain me how to retrieve all rows from the table..here in this example it retreives only the latest entered data..

while(sqlite3_step(statement) == SQLITE_ROW)
    {   
        char *field1 = (char *) sqlite3_column_text(statement,0);
        NSString *field1Str = [[NSString alloc] initWithUTF8String: field1];
        char *field2 = (char *) sqlite3_column_text(statement,1);
        NSString *field2Str = [[NSString    alloc] initWithUTF8String: field2];

        NSString *str = [[NSString alloc] initWithFormat:@"%@::%@",field1Str, field2Str];
        textv.text=str;

        [field1Str release];
        [field2Str release];
    }

推荐答案

到目前为止你做得很好.只需在 NSMutableArray 中继续添加最终格式化的字符串 (str) 并最终从函数中返回它.

You were doing all right so far. Just keep adding the final formatted string (str) in an NSMutableArray and finally return it from the function.

// Take an array to store all string.
NSMutableArray *allRows = [[[NSMutableArray alloc] init] autorelease];

while(sqlite3_step(statement) == SQLITE_ROW)
    {   
        char *field1 = (char *) sqlite3_column_text(statement,0);
        NSString *field1Str = [[NSString alloc] initWithUTF8String: field1];
        char *field2 = (char *) sqlite3_column_text(statement,1);
        NSString *field2Str = [[NSString    alloc] initWithUTF8String: field2];

        NSString *str = [NSString stringWithFormat:@"%@::%@",field1Str, field2Str];
        // textv.text=str; // I don't know why your are mixing your view controller stuff's in database function.
// Add the string in the array.
allRows addObject:str];

        [field1Str release];
        [field2Str release];
    }

// Finally you can return your allRows
return allRows;

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