88

How do you select all rows when doing linq to sql?

Select * From TableA

In both query syntax and method syntax please.

John Saunders
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chobo2
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  • All columns is the default. I don't understand the question. It would make more sense to ask how *not* to select `*`. – Gert Arnold Jan 02 '22 at 15:51

10 Answers10

110
from row in TableA select row

Or just:

TableA

In method syntax, with other operators:

TableA.Where(row => row.IsInteresting) // no .Select(), returns the whole row.

Essentially, you already are selecting all columns, the select then transforms that to the columns you care about, so you can even do things like:

from user in Users select user.LastName+", "+user.FirstName
Simon Buchan
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  • Another one that I like to do is .Take(int) to pull all columns for a given number of records. Such as TableA.Take(100) – brian s Jul 26 '13 at 13:38
  • Could you please explain why you don't need to explicitly use `from row in TableA.Rows`? Is it because `Rows` is the default property? Is that a feature of LINQ, or something baked in elsewhere? Just curious. – rory.ap Nov 18 '15 at 14:53
  • @roryap depends on your DB access library, here I'm assuming LINQ to SQL, where the table is the rows, ADO or whatever can be different. – Simon Buchan Nov 18 '15 at 17:35
74

Do you want to select all rows or all columns?

Either way, you don't actually need to do anything.

The DataContext has a property for each table; you can simply use that property to access the entire table.

For example:

foreach(var line in context.Orders) {
    //Do something
}
Community
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SLaks
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    I second that question. This is a far more helpful answer than the selected one because it's simpler and more directly answers the OP's question. – tandrewnichols Nov 18 '12 at 18:49
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    This answer deserves to be the top answer. Let's fix this :) – d.popov Mar 28 '15 at 17:16
  • Maybe it has been downvoted some day, because this answer is also not "universal", although it satisfies the OP. For me, when using it with EF, allOrders is DBSet and not an IEnumerable, so I cannot allOrders.Where() right after that. Probably I'm just using it the wrong way or missed something, but adding a .Skip(0) has made the magic for me. – Charles Roberto Canato Aug 15 '16 at 19:41
24
using (MyDataContext dc = new MyDataContext())
{
    var rows = from myRow in dc.MyTable
               select myRow;
}

OR

using (MyDataContext dc = new MyDataContext())
{
    var rows = dc.MyTable.Select(row => row);
}
Simon Fox
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    Don't do either of these. Instead, simply write `var rows = dc.MyTable`. – SLaks Oct 18 '09 at 21:05
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    he asked for query syntax and method syntax so thats what I am giving him. – Simon Fox Oct 18 '09 at 21:08
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    Don't give him what he asked for; give him what he needs. He obviously doesn't understand LINQ-to-SQL very well. – SLaks Oct 18 '09 at 21:10
  • Nope I don't understand LINQ-to-SQL very well yet. Don't have the time to read books about it yet just sort of when I need information then I start looking around. Plus I am waiting till the Enity frameworks better. Since I rather learn that since it can use all databass. – chobo2 Oct 19 '09 at 20:44
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    Fair enough, however there is nothing wrong with either of the solutions I have provided. They give you a good base to start from in terms of building up a query of greater complexity. – Simon Fox Oct 19 '09 at 22:06
4

u want select all data from database then u can try this:-

dbclassDataContext dc= new dbclassDataContext()
List<tableName> ObjectName= dc.tableName.ToList();

otherwise You can try this:-

var Registration = from reg in dcdc.GetTable<registration>() select reg;

and method Syntex :-

 var Registration = dc.registration.Select(reg => reg); 
Joy
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2
Dim q = From c In TableA
Select c.TableA

ObjectDumper.Write(q)
sjngm
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SattiS
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2

Assuming TableA as an entity of table TableA, and TableADBEntities as DB Entity class,

  1. LINQ Method
IQueryable<TableA> result;
using (var context = new TableADBEntities())
{
   result = context.TableA.Select(s => s);
}
  1. LINQ-to-SQL Query
IQueryable<TableA> result;
using (var context = new TableADBEntities())
{
   var qry = from s in context.TableA
               select s;
   result = qry.Select(s => s);
}

Native SQL can also be used as:

  1. Native SQL
IList<TableA> resultList;
using (var context = new TableADBEntities())
{
   resultList = context.TableA.SqlQuery("Select * from dbo.TableA").ToList();
}

Note: dbo is a default schema owner in SQL Server. One can construct a SQL SELECT query as per the database in the context.

1

You can use simple linq query as follow to select all records from sql table

var qry = ent.tableName.Select(x => x).ToList();

anagha
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0

Why don't you use

DbTestDataContext obj = new DbTestDataContext();
var q =from a in obj.GetTable<TableName>() select a;

This is simple.

0

I often need to retrieve 'all' columns, except a few. so Select(x => x) does not work for me.

LINQPad's editor can auto-expand * to all columns.

enter image description here

after select '* all', LINQPad expands *, then I can remove not-needed columns.

enter image description here

Rm558
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0

Simple -

var data=db.table.ToList();

data is variable

db is your dbcontext variable

table is dbset Table from which data you want to fetch.

And finally converting in list.