# Does Clover Loads Attribute with Null value?

**URL:** <https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178>\
**Category:** CloverDX Platform\
**Created:** [February 13, 2013, 12:00am UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178 "2013-02-13T00:00:00Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![varkashy](https://avatars.discourse-cdn.com/v4/letter/v/3ec8ea/32.png) [@varkashy](https://forum.cloverdx.com/u/varkashy)\
**Post date:** [February 13, 2013, 12:00am UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178/1 "2013-02-13T00:00:00Z")

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A very basic question.  
I am reading data from a table, few of the columns are null for all records. On edge i can see these data being passed. However, on Attribute on datastore i donot see these attributes.  
I just wanted to confirm, is it like clover will not load attributes for which the values are null for all records?

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**Author:** ![imriskal](https://avatars.discourse-cdn.com/v4/letter/i/b38774/32.png) [@imriskal](https://forum.cloverdx.com/u/imriskal)\
**Post date:** [February 13, 2013, 9:05am UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178/2 "2013-02-13T09:05:22Z")

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Hi, varkashy,

What is the difference between words “column” and “attribute” in your question? Do you consider them as the same thing? And what is “attribute on datastore”? Can you please rephrase your question? I am not sure I understand correctly.

If your problem is that some of the columns from input data are missing, this would be an odd behavior. Readers should not skip any columns if everythig is set properly. Can you please post an example graph and some sample of your input file? It would be very helpful here. Thanks in advance.

Best regards,

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**Author:** ![varkashy](https://avatars.discourse-cdn.com/v4/letter/v/3ec8ea/32.png) [@varkashy](https://forum.cloverdx.com/u/varkashy)\
**Post date:** [February 13, 2013, 11:03am UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178/3 "2013-02-13T11:03:02Z")

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To clarify in to my question  
I have a table in DB , with a column , lets say, supply\_id. This is null for all rows.  
When i load data from this table using clover ETL graph and lets say source this data to another table , will my final table will have a column as supply\_id?  
Or will this column will get dumped.

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**Author:** ![imriskal](https://avatars.discourse-cdn.com/v4/letter/i/b38774/32.png) [@imriskal](https://forum.cloverdx.com/u/imriskal)\
**Post date:** [February 13, 2013, 12:35pm UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178/4 "2013-02-13T12:35:30Z")

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Your final table has to exist before the query in DBOutputTable is executed. You can create it externally (outside Designer) or right in Designer with “Create database table” function. But we do not support automatic table creation during the graph run (the process generally can not be fully automatized). So if we realize that the table has to exist before, everything else is just a matter of field mapping.

Best regards,

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**Author:** ![varkashy](https://avatars.discourse-cdn.com/v4/letter/v/3ec8ea/32.png) [@varkashy](https://forum.cloverdx.com/u/varkashy)\
**Post date:** [February 13, 2013, 1:30pm UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178/5 "2013-02-13T13:30:18Z")

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My question is not about table creation. But if that column which has all null value will be picked in ETL load or not?

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**Author:** ![imriskal](https://avatars.discourse-cdn.com/v4/letter/i/b38774/32.png) [@imriskal](https://forum.cloverdx.com/u/imriskal)\
**Post date:** [February 14, 2013, 8:55am UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178/6 "2013-02-14T08:55:41Z")

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Yes, if you have it in your metadata, it will be picked. Btw. there is Nullable property on the metadata field which if set to false and reader finds the null value, throws an error.

Best regards,

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**Author:** ![swathi\_shankar](https://avatars.discourse-cdn.com/v4/letter/s/c2a13f/32.png) [@swathi\_shankar](https://forum.cloverdx.com/u/swathi_shankar)\
**Post date:** [February 14, 2013, 9:13am UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178/7 "2013-02-14T09:13:59Z")

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Hi,

The attribute which has null values for all of the rows will be dropped and not pumped into ur data store. Even we have noticed this.

But actually this behavior is unexpected and must be changed.

Thanks,

Swathi

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**Author:** ![David\_Hlidek](https://avatars.discourse-cdn.com/v4/letter/d/58f4c7/32.png) [@David\_Hlidek](https://forum.cloverdx.com/u/David_Hlidek)\
**Post date:** [February 14, 2013, 10:05am UTC](https://forum.cloverdx.com/t/does-clover-loads-attribute-with-null-value/1178/8 "2013-02-14T10:05:25Z")

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Hi both,

seems to me, you both use Endeca/Oracle Data Integrator Server, right? By that was caused misunderstandings above, we thought you use plain CloverETL.

Please contact Oracle support, if you really use Data Integrator. They will help you better as they know all the details about CloverETL integration into their product.

Regarding this problem, CloverETL really reads all columns, including those filled only by null values. Question is how this columns are handled by Integrator Server.
