Thanks for your suggestion Micha.
I haven't tried the binary export function but I tried the CSV export using the following SQL command:
EXPORT "<schema_name>"."*" AS CSV INTO '/tmp/TEMP' WITH THREADS 10;
but got the following error (even though I used chmod 777):
SAP DBTech JDBC: [2048]: column store error: table export failed: [30109] Could not create export path;/tmp/TEMP/index...."
I will try with the binary export option but not sure that is the solution to the above error.