Convert SQL code (as string) into table - dynamic pivot

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I have used the below SQL script to perform dynamic pivot. I want to use the result to left join on another table, but the "INTO" method does not seem to work for the table variable @query. It shows an error:

Must declare the table variable "@query"

If I directly join the table like this: LEFT JOIN @query. How should I save @query in order to left join on another table? Thanks!

create table temp
(
    date datetime,
    category varchar(3),
    amount money
)

insert into temp values ('1/1/2012', 'ABC', 1000.00)
insert into temp values ('2/1/2012', 'DEF', 500.00)
insert into temp values ('2/1/2012', 'GHI', 800.00)
insert into temp values ('2/10/2012', 'DEF', 700.00)
insert into temp values ('3/1/2012', 'ABC', 1100.00)


DECLARE @cols AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX);

SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(c.category) 
            FROM temp c
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT date, ' + @cols + ' from 
            (
                select date
                    , amount
                    , category
                from temp
           ) x
            pivot 
            (
                 max(amount)
                for category in (' + @cols + ')
            ) p '


execute(@query)

drop table temp
1

There are 1 answers

0
cheunghm4532 On BEST ANSWER

I got it figured out. The solution is to add ##result in the string sql script as below:

set @query = 'SELECT date, ' + @cols + ' ##result from 
            (
                select date
                    , amount
                    , category
                from temp
           ) x
            pivot 
            (
                 max(amount)
                for category in (' + @cols + ')
            ) p '

select * from ##result