Any way to get query data dynamically while its executing.

Do you want the paging function？
You can refer to OFFSETClause

@qinchaofeng yes the client referred paging function.

Not really sure if offsetclause will help to get query data dynamically.

This sounds to me as a front-end functionality rather than a Vertica sided one.
In a JDBC / ODBC front end application, you SQLPrepare and SQLExecute a query - returning maybe 10,000 rows - and then you set the rowset to , say, 100 rows ; then repeated calls of SQLFetch() will return 100 rows at a time.
Is that what you are looking for?

thanks @marcothesane that actually makes sense.

There is a way in vertica to fetch result sets in batches using OFFSET.
But there can be some tricks to accomplish this depending upon customer's use case too:
1) In client software like DBeaver we have an option to set number of records to fetch by setting "Resultset Fetch Size".
2) I can think of a another way to accomplish that using below trick with rownum:
Set below variables as per need:

Suppose I want batch of 10 rows at a time:
\set NumRows 10

Now I want 2nd resulset, means rows from 20-30
\set i 2

Now use below example query to fetch records: I am using eep as table name.

SELECT * FROM
(
SELECT
row_number() OVER(ORDER BY transaction_id) AS RW,
eep.*
FROM eep
) myAlias
WHERE myAlias.RW BETWEEN (:NumRows * :i) AND ((:NumRows * :i)+ :NumRows)

Hope it helps.

thanks @Abhishek_Rana for detailed explanation.

In addition maybe parallel insert select can provide a way to analyze portions of the result set.
Example 1:

    INSERT INTO MY_TABLE  
           SELECT a,b,c
           FROM OTHER_TABLE
           WHERE hash(a)/((9223372036854775807/YOUR_NODE_COUNT) + 1)= YOUR_SEGMENT;

Example 2:

    INSERT INTO foo_cp
    SELECT * from foo
    WHERE HASH( some_column ) % 4 = 0;

    INSERT INTO foo_cp
    SELECT * from foo
    WHERE HASH( some_column ) % 4 = 1;

    INSERT INTO foo_cp
    SELECT * from foo
    WHERE HASH( some_column ) % 4 = 2;

    INSERT INTO foo_cp
    SELECT * from foo
    WHERE HASH( some_column ) % 4 = 3;