asked on

SQL Update query question.

Can someone decipher and explain what this query is doing.
I need to explain this in non-sql terms..

UPDATE customer_applications
SET loan_purpose = fetch_loan_purpose_subquery.loan_purpose
FROM (
SELECT id AS customer_application_id,
CASE
WHEN loan_purpose_from_step_1_subquery.loan_purpose is null
THEN substring( substring(information FROM
': &' || substring(information from E':step_1: \\*([0-9]+)') ||
'.*:step_1:' ) from E'loan_purpose: ([^\n]+)')
ELSE loan_purpose_from_step_1_subquery.loan_purpose
END AS loan_purpose
FROM (
SELECT
customer_applications.id,
customer_applications.information,
/* Look for things of the form
loan_purpose: ([^\n]+)'
occurring after :step_1 */
substring(
substring(customer_applications.information FROM E':step_1.*')
FROM E'loan_purpose: ([^\n]+)')
AS loan_purpose
FROM customer_applications
INNER JOIN loans ON loans.customer_application_id = customer_applications.id
ORDER BY id DESC) loan_purpose_from_step_1_subquery
) fetch_loan_purpose_subquery
WHERE customer_applications.id =
fetch_loan_purpose_subquery.customer_application_id;

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Below is an example of a value in customer_applications.detail (which is a text blog):

:lead_raw: !ruby/
hash:ActiveSupport::HashWithIndifferentAccess
Loan_Amount_Requested: '5000'
Purpose_Of_Loan: ''
First_Name: John
Last_Name: Carson
Email: jcarson@gmail.com
Primary_Phone: '5555555555'
Home_Street_Address: 111 ABC Street
Home_City: New Orleans
Home_State: LA
Home_Zip: '70119'
Home:Type: rent
Income_Net_Monthly: '2501'
Employer_Time: '24'
PayFrequency: BIWEEKLY
Employer_Name: ABC Steel
Employer_Phone: '5555555555'
Employer_Street_Address: 123 Main Street
Employer_City: New Orleans
Employer_State: LA
Employer_Zip: '70119'
SSN: '999999999'
Bank_Name: Bank ABC
Bank_Routing_Number: '5555555555'
Bank_Account_Number: '5555555555'
Bank_Account_Type: checking
Date_of_Birth: 1915-10-08
Income_Type: employment
Home_Time: '24'
controller: leads
action: inbound
lead_provider: personal_96_151
:lead: &99451720
:loan_amount_requested: '5000'
:loan_purpose: 'boat repair'
:email: jcarson@gmail.com
:person_attributes:
:first_name: John
:last_name: Carson
:home_phone: '5555555555'
:ssn: '55555555'
date_of_birth: 1985-10-08
:bank_accounts_attributes:
0:
:name: FIRST NAT BANK
:routing_number: '555555555'
:account_numbner: '555555555'
account_type: checking
:incomes_attributes:
0:
:monthly_net_income: '2501'
:time_at_job: '24'
income_type: employment
:pay_frequency: BIWEEKLY
:employer_attributes:
:name: ABC Steel
:phone_number: '5555555555'
address_attributes:
:state: LA
:address_1: 2811 ABC Street
:city: New Orleans
:zip: '70119'
:rent_or_own: rent
:time_at_address: '24'
:stepC_1 *99451720

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Vikas Garg

HI,

is this query working fine ?

Since I could not get this working due to errors in it.

swaggrK

ASKER

It is more of a conceptional question. I am trying to figure out what it is trying to accomplish in non-technical terms.

Vitor Montalvão

That's not SQL Server. May be MySQL but can be sure of that.

Vitor Montalvão

Looks like is updating loan_purpose where the value is null with this value returned from this formula:
substring( substring(information FROM ': &' || substring(information from E':step_1: \\*([0-9]+)') ||'.*:step_1:' ) from E'loan_purpose: ([^\n]+)')

Vikas Garg

HI,

@Vitor, it can be seen that the query is trying to update based on the logic
and I think the help is asked for understanding of that Logic...

swaggrK

ASKER

Correct. I am trying to understand the logic in very basic terms..

Vikas Garg

Hi,

But SwaggrK, I am unable to identify the logic since the part of the query with substring is wrong

May be you should write actual running query if exist for logic description and if you do not have any query and want to develop is as per the logic then have to provide with example.

ASKER CERTIFIED SOLUTION

PortletPaul

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