How to transport a long String(Base64) from ESP to HANA?

[Former Member]

Hi everyone,

I work at a project where we need to handle pictures in base64-code. The code of every picture has 70,000+ chars.

In ESP we are using "String"-datatype for the pictures, which makes no problem.

Now we need the Stirngs in our HANA-databse.

We tried to use the standard HANA-Output-Adapter. But the HANA-varchar-datatype has a maximum of 5,000 chars. So we can not use varchar.

If whe use CLOB in HANA i can manualy inserte the whole String into the table.

But the standard HANA-Output-Adapter dose not work with CLOB. It says: "Unsupported Datatype".

Is there a "workaround" out there or do we have to write a specific adapter to solve the problem?

With kind regards,

Matthias

[andrzej_kucharczyk · Accepted solution]

Hi Matthias,

Unfortunately HANA output adapter does not work with clob and blob data types. For performance reasons HANA output adapter pre-allocates memory required for all rows it buffers that are waiting to be transferred. This could be dozens of millions of rows depending on your adapter properties such as bulkInsertArraySize and threadCount. On start up the adapter asks HANA for maximum size of every column in your target table. This works fine for types such as varchar or integer with well defined maximum size but it does not work for clobs or blobs where maximum size could be 2GB.

For future releases of ESP we are considering adding support of clobs, and blobs to HANA output adapter but this would not perform as fast as it currently does for tables with varchar or varbinar columns.

For now as a workaround you can use a generic db_out adapter which supports mapping of ESP string to HANA clob. It is not as fast as HANA adapter because it is single threaded but it might be sufficient for your use case.

Regards,

Andrzej.