Welcome to the forum.
Excel has a hard time concatenating variable size arrays. Using basic functions, you could create 45 additional columns to the right of the ID columns, each of which looks up the ID if it's there, and concatenates it to the results of the previous cell. Then column B would use the result of the last column.
If you have Excel 2016, or Excel Live, Microsoft added a new function called TEXTJOIN. Using that, you can get the results you want like this:
| A | B |
---|
ID | Name | |
Al | | |
Brianne | | |
Cal | | |
Dyan | | |
Ed | | |
Felice | | |
Greg | | |
Hal | | |
<colgroup><col style="width: 25pxpx"><col><col></colgroup><thead>
</thead><tbody>
[TD="align: center"]1[/TD]
[TD="align: center"]2[/TD]
[TD="align: right"]10[/TD]
[TD="align: center"]3[/TD]
[TD="align: right"]20[/TD]
[TD="align: center"]4[/TD]
[TD="align: right"]34[/TD]
[TD="align: center"]5[/TD]
[TD="align: right"]45[/TD]
[TD="align: center"]6[/TD]
[TD="align: right"]25[/TD]
[TD="align: center"]7[/TD]
[TD="align: right"]29[/TD]
[TD="align: center"]8[/TD]
[TD="align: right"]30[/TD]
[TD="align: center"]9[/TD]
[TD="align: right"]55[/TD]
</tbody>
Sheet2
That's just the lookup sheet. Here's the formula:
<colgroup><col style="width: 25pxpx"><col><col><col><col><col><col></colgroup><thead>
</thead><tbody>
[TD="align: center"]1[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]ID[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]Vlookups?[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]Col1[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]Col2[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]Col3[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]Col4[/TD]
[TD="align: center"]2[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]1[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]Cal; Dyan[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]34[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]45[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"][/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"][/TD]
[TD="align: center"]3[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]2[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]Brianne; Ed; Felice; Greg[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]20[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]25[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]30[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]29[/TD]
[TD="align: center"]4[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]3[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] "]Al[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"]10[/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"][/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"][/TD]
[TD="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=FAFAFA]#FAFAFA[/URL] , align: right"][/TD]
</tbody>
Sheet1
[TABLE="width: 85%"]
<tbody>[TR]
[TD]
Array Formulas[TABLE="width: 100%"]
<thead>[TR="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=DAE7F5]#DAE7F5[/URL] "]
[TH="width: 10px"]Cell[/TH]
[TH="align: left"]Formula[/TH]
[/TR]
</thead><tbody>[TR]
[TH="width: 10px, bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=DAE7F5]#DAE7F5[/URL] "]B2[/TH]
[TD="align: left"]{=TEXTJOIN(
"; ",TRUE,IF(C2:G2=Sheet2!$A$2:$A$20,Sheet2!$B$2:$B$20&"",""))}[/TD]
[/TR]
</tbody>[/TABLE]
Entered with Ctrl+Shift+Enter. If entered correctly, Excel will surround with curly braces {}.
Note: Do not try and enter the {} manually yourself[/TD]
[/TR]
</tbody>[/TABLE]
In some basic testing, it works OK, but occasionally the order of the names doesn't match the order of the IDs.
If you don't have TEXTJOIN, or if the order is an issue, and you don't want to use the extra 45-column method, we'd have to write a UDF to do this. If you want to try that, let me know and I'll write it up.
Hope this helps.