Thanks for reply.
There are 15 columns per table and loop is on 2000 tables.
I am calling
getColumns(database name, null, table name, "%") this method to fetch each table's column list.
One more thing I would like to add is, this method works well for less number of iterations
Note: getColumns() method I am calling on databaseMetaData object which I retrieved from MSSQL connection object.