How to use Peek function?

[#1]

hi,

I do not know peek function ,how to use  that function please explain me with example.about peek function.

                               Thankyou,

Regards:

Madhu.

[SunilChauhan]

peek( fieldname [ , row [ , tablename ] ] )

Returns the contents of the fieldname in the record specified by row in the input table tablename. Data are fetched from the associative QlikView database.

Fieldname must be given as a string (e.g. a quoted literal).

Row must be an integer. 0 denotes the first record, 1 the second and so on. Negative numbers indicate order from the end of the table. -1 denotes the last record read.

If no row is stated, -1 is assumed.

Tablename is a table label without the ending colon. If no tablename is stated, the current table is assumed. If used outside the load statement or referring to another table, the tablename must be included.

Examples:

peek( 'Sales' )
returns the value of Sales in the previous record read ( equivalent to previous(Sales) ).

peek( 'Sales', 2 )
returns the value of Sales from the third record read from the current input table.

peek( 'Sales', -2 )
returns the value of Sales from the second last record read into the current input table.

peek( 'Sales', 0, Tab1 )
returns the value of Sales from the first record read into the input table labeled Tab1.

Load A, B, numsum( B, peek( 'Bsum' ) ) as Bsum...;
creates an accumulation of B in Bsum.

[#3]

Hi Madhu,

Go through this.

http://community.qlik.com/blogs/qlikviewdesignblog/2013/04/08/peek-vs-previous-when-to-use-each

Thanks,

Ram

[#4]

I use like this   LOAD   Peek(Product,-1)Resident Product; but it does not work. i attached snipping files below this box.

[SunilChauhan]

add on extra field and cchange syntax in resident

use

Load Peek('Product','-1',Product) as fieldname,

1 as J

resident  Product;

drop field J;

hope this helps

or

Load Peek('Product','-1') as fieldname,

1 as J

resident  Product;

drop field J;

[#6]

Hi,

check out this

[#7]

Date	DepositBalnc
15/06/2005	500
18/06/2005	1500
20/06/2005	200
21/06/2005	600
25/06/2005	100

Let suppose you have a table with a field name as DepositBalnc,and Your requirement is to create a new field with available balance by formula available=DepositBalnc+available and initially available is 0,output table is

Date	Available	DepositBalnc
15/06/2005	0	500
18/06/2005	500	1500
20/06/2005	2000	200
21/06/2005	2200	600
25/06/2005	2800	100

now peek() loads the already loaded field value in the table. now the Available field can be created by following Script

If(RowNo() = 1, 0, Peek(Available)+DepositBalnc) as Available,

Hope now you will understand peek() use..

[#8]

Thank you sunil

[#9]

peek() function works within the load block if you dont mention the table name.

but out of the load block you have to use table name like

peek(Product,-1,'Product') try this

[SunilChauhan]

please mark it as helpful correct if you got solution