Question

我正在尝试找出一个最常用的方法来连接（至少）两个管道分隔的文本文件在一个公共值上，类似于SQL的连接。我会将这两个文件加载到列表中然后拆分字符串吗？我有点卡住了。

我的数据是这样的：

Text1.txt文件

Bacon|Delicious|salty|lowcalorie
Sausage|Delicious|salty|highfat
Chicken|Chicken|chicken|highprotein

text2.txt文件

Bacon|pork|cheap|crispy
Sausage|pork|cheap|null
Chicken|Chicken|moderate|sandwiches

我真的想运行SQL查询而只是做一个

Select * from Text1
FULL OUTER JOIN text2
ON text1.firstColumn=table2.firstColumn;

Answer 1

用C＃标记了这个问题？： - ）

可能这个？ LINQ的完全外连接：

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

static IEnumerable<string[]> ReadTabFile(string fileName, char delimiter)
{
  return File.ReadLines(fileName).Select(line => line.Split(delimiter));
}

static void Main()
{
  string[][] lines1 = ReadTabFile("text1.txt", '|').ToArray();
  string[][] lines2 = ReadTabFile("text2.txt", '|').ToArray();

  var leftOuterJoin = from line1 in lines1
                      join line2 in lines2
                      on line1.FirstOrDefault() equals line2.FirstOrDefault()
                      select new
                      {
                        line1,
                        line2
                      };

  var rightOuterJoin = from line2 in lines2
                       join line1 in lines1
                       on line2.FirstOrDefault() equals line1.FirstOrDefault()
                       select new
                       {
                         line1,
                         line2
                       };

  var fullOuterJoin = leftOuterJoin.Union(rightOuterJoin);

  foreach (var test in fullOuterJoin)
  {
    Console.WriteLine("{0,-40} - {1,-40}", string.Join("|", test.line1), string.Join("|", test.line2));
  }
}

结果：

Bacon|Delicious|salty|lowcalorie         - Bacon|pork|cheap|crispy
Sausage|Delicious|salty|highfat          - Sausage|pork|cheap|null
Chicken|Chicken|chicken|highprotein      - Chicken|Chicken|moderate|sandwiches

Answer 2

Pure T-SQL解决方案如下所示：

CREATE TABLE #TEXTFILE_1(
    FIELD1 varchar(100) ,
    FIELD2 varchar(100) ,
    FIELD3 varchar(100) ,
    FIELD4 varchar(100));

BULK INSERT #TEXTFILE_1 FROM 'C:\FILE1.TXT'
WITH (FIELDTERMINATOR ='|',ROWTERMINATOR =' \n')

CREATE TABLE #TEXTFILE_2(
    FIELD1 varchar(100) ,
    FIELD2 varchar(100) ,
    FIELD3 varchar(100) ,
    FIELD4 varchar(100));

BULK INSERT #TEXTFILE_2 FROM 'C:\FILE2.TXT'
WITH (FIELDTERMINATOR ='|',ROWTERMINATOR =' \n')


SELECT * FROM #TEXTFILE_1 text1
FULL OUTER JOIN #TEXTFILE_2 text2
ON text1.FIELD1=text2.FIELD1

DROP TABLE #TEXTFILE_1
DROP TABLE #TEXTFILE_2

加入指定值

2 个答案: