How to use Hash128 function in resolving synthetic key issue?

[#1]

Hi All,

How to use Hash128 function in resolving synthetic key issue?

Please give an example. It would be great if provide a sample file.

Thanks in advance.

[#2]

insead of creating composit key like

field1 and filed2 and field3 as key       go with hash128

autonumberhash128(field1,field2,field3) as key

[its_anandrjs · Accepted solution]

Hi,

You can use it like below examples

From Qlikview Help

autonumberhash128(expression {, expression})

Calculates a 128-bit hash of the combined input expression values and the returns a unique integer value for each distinct hash value encountered during the script execution. This function can be used e.g. for creating a compact memory representation of a complex key.

Example:

autonumberhash128 ( Region, Year, Month )

Note:- Here Region, Year, Month individual table fields.

Regards

Anand

[#4]

Hi,

If you have to create composite key just create a composite key using of autonumber function bcoz it is a optimization technique.it will give good performance while loading the data

Autonumberhash(field1,field2,field3) as Key_Field (or)

Autonumberhash128(field1,field2,field3) as Key_Field (or)

Autonumberhash256(field1,field2,field3) as Key_Field