SQL error There is already an object with the name

  

Basically the error you have is because a table of type    #Temp stays physically stored and you have to do DROP   manual, this does not happen with the type variable TABLE since its   memory management is volatile and it is not necessary to make a DROP every time   that you execute your code.

Source: User contribution Flxtr in your comment .

An alternative to solve this error could be:

• Create a variable of type TABLE .

I have modified your code with my suggestion:

DECLARE @TablaResultado AS TABLE (
    idTienda AS INT,
    importe AS FLOAT
);

IF @fecha between '2017-01-01' and '2018-06-30'
    BEGIN   
        INSERT INTO @TablaResultado
        SELECT id_tienda,sum(importe) as importe
        FROM
        (SELECT id_tienda, 0 as importe, 0 as unidades from #tdaZona
            group by id_tienda
            UNION
            SELECT [IdTienda] as id_tienda,sum(ns) as importe, sum(qty) as unidades
            FROM dbo.BaseVentasHistoria
            where Fecha>=@fechaAnt and fecha < @fechaCAnt and idTienda in (select id_tienda from #tdaZona)
            group by idtienda) as A
        group by id_tienda;
    END
ELSE
BEGIN
    INSERT INTO @TablaResultado
    SELECT id_tienda,sum(ventas) as ventas
    FROM
    (SELECT id_tienda collate Modern_Spanish_CI_AS as id_tienda, 0 as ventas from #tdaZona
        group by id_tienda
        UNION
        select n_tickets.id_tienda,ISNULL(sum(importeeuros),0) as ventas 
        from dbo.baseVentasDiarias with(nolock)  
        inner join n_tickets on n_tickets.id_auto = baseVentasDiarias.id_auto 
        where Fecha>=@fechaAnt and fecha < @fechaCAnt and n_tickets.id_tienda in (select id_tienda collate Modern_Spanish_CI_AS as id_tienda from #tdaZona)
        group by n_tickets.id_tienda) as A
    group by id_tienda
END

-- Cuando se ejecute tu procedimiento almacenado,
-- Los resultados estarán en esta variable.
SELECT * FROM @TablaResultado

Rodrigo, conceptually a SELECT * INTO tabla is a CREATE TABLE ... + INSERT INTO ... . In your Sp you have two of these statements that point to the same #vtaAA table so the compiling engine gives you an error in the second SELECT * INTO tabla , because it "interprets" that you are creating the same table twice. It's like doing this:

create table #T(id int)
create table #T(id int)

The error obtained is similar to yours and of course the table #T is not created. The solution is to replace the SELECT * INTO with a CREATE TABLE and then a classic INSERT INTO .

create table #T(id int)

if <condicion> begin
   insert into #t (id)
   select id
          from tabla1
end else begin
   insert into #t (id)
   select id
          from tabla2
end