Once we import data from RDBMS to HADOOP and after that if data will be updated in RDBMS then data in Hadoop will updated automatically or we have to update it manually??
Sqoop will add (using --incremental) the new data added to the source RDBMS, but will not update the data already ingested.
You'll need manual process, or third-party tooling to keep your Hadoop copy in sync with the RDBMS.
Adding to @Christophe Vico's answer above. You can use the below "manual" merge/update strategies after you import the data.
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