Performance problem whlile selecting(extracting the data)

Question

i have one intermediate table.
iam inserting the rows which are derived from a select statement
The select statement having a where clause which joins a view (created by 5 tables)
The problem is select statement which is getting the data is taking more time
i identified the problems like this
1) The view which is using in the select statement is not indexed---is index is necessary on view ????
2) Because the tables which are used to create a view have already properly indexed
3) while extracting the data it is taking the more time
the below query will extract the data and insert the data in the intermediate table
SELECT 1414 report_time,
2 dt_q,
1 hirearchy_no_q,
p.unique_security_c,
p.source_code_c,
p.customer_specific_security_c user_security_c,
p.par_value par_value, exchange_code_c,
(CASE WHEN p.ASK_PRICE_L IS NOT NULL THEN 1
WHEN p.BID_PRICE_L IS NOT NULL THEN 1
WHEN p.STRIKE_PRICE_L IS NOT NULL THEN 1
WHEN p.VALUATION_PRICE_L IS NOT NULL THEN 1 ELSE 0 END) bill_status,
p.CLASS_C AS CLASS,
p.SUBCLASS_C AS SUBCLASS,
p.AGENT_ADDRESS_LINE1_T AS AGENTADDRESSLINE1,
p.AGENT_ADDRESS_LINE2_T AS AGENTADDRESSLINE2,
p.AGENT_CODE1_T AS AGENTCODE1,
p.AGENT_CODE2_T AS AGENTCODE2,
p.AGENT_NAME_LINE1_T AS AGENTNAMELINE1,
p.AGENT_NAME_LINE2_T AS AGENTNAMELINE2,
p.ASK_PRICE_L AS ASKPRICE,
p.ASK_PRICE_DATE_D AS ASKPRICEDATE,
p.ASSET_CLASS_T AS ASSETCLASS
FROM (SELECT
DISTINCT x.*,m.customer_specific_security_c,m.par_value
FROM
HOLDING_M m JOIN ED_DVTKQS_V x ON
m.unique_security_c = x.unique_security_c AND
m.customer_c = 'CONF100005' AND
m.portfolio_c = 24 AND
m.status_c = 1
WHERE exists
     (SELECT 1 FROM ED_DVTKQS_V y
          WHERE x.unique_security_c = y.unique_security_c
               GROUP BY y.unique_security_c
               HAVING MAX(y.trading_volume_l) = x.trading_volume_l)) p
any one please give me the valueble suggestions on the performance

Answer 1

thanks for the updating
in the select query we used some functions like max
(SELECT 1 FROM ED_DVTKQS_V y
WHERE x.unique_security_c = y.unique_security_c
GROUP BY y.unique_security_c
HAVING MAX(y.trading_volume_l) = x.trading_volume_l)) p
will these type of functions will cause the performance problem ???