If you want to import all table definitions, Go to

File menu -> Choose Import
expand the SAP HANA Content node
choose "Mass Import of Metadata" and choose next
select the target system where you want to import all the table definitions, and choose next
inn the Connections Details Dialog , enter the user name and password of the target system
Select the required source system and choose Finish.

Note: If you want to import selective table definitions use "Selective Import of Metadata".

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