question

@ecmprem, since you haven't provided enough information about your schema, I am going to make an assumption here. In my below example demonstration, I have used DataStax Astra (DBaaS) to work with and DataStax Bulk Loader version 1.8.0.

Assumption #1:

Table Schema:

CREATE TABLE db3.ecmprem (
    i int PRIMARY KEY,
    checklist frozen<list<frozen<checklist>>>
);

UDT Schema:

CREATE TYPE db3.checklist (
    dynamic_questionnaire_answers frozen<list<frozen<"QuestionnaireAnswer">>>
);

CREATE TYPE db3."QuestionnaireAnswer" (
    question_id text,
    question_text text,
    gui_control text,
    options list<text>,
    answer_max int,
    answer_min int
);

Sample Input file in CSV:

Note: I have saved the below content into a .csv file to be used later with DSBulk load operation. Note the header is also present and will match with my C* table column names here.

i,checklist
1,"[{\"dynamic_questionnaire_answers\":[{\"question_id\":\"1\",\"question_text\":\"Testing one scenario for questionnaire. *\",\"gui_control\":\"radio\",\"options\":[\"Yes\",\"No\"],\"answer_max\":1,\"answer_min\":1}]}]"

DSBulk Load command used:

% ./dsbulk --version
DataStax Bulk Loader v1.8.0

% ./dsbulk load -k db3 -t ecmprem -b "/path/to/Downloads/secure-connect-db3.zip" -url '~/Downloads/ecmprem_unload/output-000001.csv' -u 'CHANGE_ME' -p 'CHANGE_ME' --datastax-java-driver.basic.request.consistency LOCAL_QUORUM

Output from running the above load command:

Username and password provided but auth provider not specified, inferring PlainTextAuthProvider
A cloud secure connect bundle was provided: ignoring all explicit contact point
Operation directory: /path/to/DSBulk/dsbulk-1.8.0/bin/logs/LOAD_20220110-143706-721059
total | failed | rows/s | p50ms | p99ms | p999ms | batches
    1 |      0 |      3 | 45.22 | 45.35 |  45.35 |    1.00
Operation LOAD_20220110-143706-721059 completed successfully in less than one second.
Last processed positions can be found in positions.txt

Validation:

By running a SELECT operation on my sample table via the CQL Console on the DataStax AstraDB I get the following:

token@cqlsh:db3> SELECT * FROM db3.ecmprem;

 i | checklist
---+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 1 | [{dynamic_questionnaire_answers: [QuestionnaireAnswer(question_id=u'1', question_text=u'Testing one scenario for questionnaire. *', gui_control=u'radio', options=[u'Yes', u'No'], answer_max=1, answer_min=1)]}]

(1 rows)

Inserting directly via CQL:

The below mechanism to insert directly using CQL also works,

INSERT INTO db3.ecmprem (i, checklist) VALUES (
    1,
    [{
        dynamic_questionnaire_answers : [
            {
                question_id : '1', 
                question_text : 'Testing one scenario for questionnaire. *',
                gui_control : 'radio', 
                options: ['Yes','No'], 
                answer_max : 1, 
                answer_min : 1
            }
        ]
    }]
);

Assumption #2:

Table Schema:

CREATE TABLE db3.ecmprem (
    i int PRIMARY KEY,
    checklist frozen<list<frozen<checklist>>>
);

UDT Schema:

CREATE TYPE db3.checklist (
    dynamic_questionnaire_answers frozen<list<frozen<map<text, frozen<"QuestionnaireAnswer">>>>>
);

CREATE TYPE db3."QuestionnaireAnswer" (
    question_id text,
    question_text text,
    gui_control text,
    options list<text>,
    answer_max int,
    answer_min int
);

Sample Input file in CSV:

Note: I have saved the below content into a .csv file to be used later with DSBulk load operation. Note the header is also present and will match with my C* table column names here.

i,checklist
1,"[{\"dynamic_questionnaire_answers\":[{\"QuestionnaireAnswer\":{\"question_id\":\"1\",\"question_text\":\"Testing one scenario for questionnaire. *\",\"gui_control\":\"radio\",\"options\":[\"Yes\",\"No\"],\"answer_max\":1,\"answer_min\":1}}]}]"

DSBulk Load command used:

% ./dsbulk --version
DataStax Bulk Loader v1.8.0

% ./dsbulk load -k db3 -t ecmprem -b "/path/to/Downloads/secure-connect-db3.zip" -url '~/Downloads/ecmprem_unload/output-000001.csv' -u 'CHANGE_ME' -p 'CHANGE_ME' --datastax-java-driver.basic.request.consistency LOCAL_QUORUM

Output from running the above load command:

Username and password provided but auth provider not specified, inferring PlainTextAuthProvider
A cloud secure connect bundle was provided: ignoring all explicit contact points.
Operation directory: /path/to/dsbulk-1.8.0/bin/logs/LOAD_20220110-152459-043829
total | failed | rows/s | p50ms | p99ms | p999ms | batches
    1 |      0 |      4 | 47.84 | 47.97 |  47.97 |    1.00
Operation LOAD_20220110-152459-043829 completed successfully in less than one second.
Last processed positions can be found in positions.txt

Validation:

By running a SELECT operation on my sample table via the CQL Console on the DataStax AstraDB I get the following:

token@cqlsh:db3> SELECT * FROM db3.ecmprem ;

 i | checklist
---+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 1 | [{dynamic_questionnaire_answers: [{'QuestionnaireAnswer': QuestionnaireAnswer(question_id=u'1', question_text=u'Testing one scenario for questionnaire. *', gui_control=u'radio', options=[u'Yes', u'No'], answer_max=1, answer_min=1)}]}]

(1 rows)

Inserting directly via CQL:

The below mechanism to insert directly using CQL also works,

INSERT INTO db3.ecmprem (i, checklist) VALUES (
    1,
    [{
        dynamic_questionnaire_answers : [
            {
                'QuestionnaireAnswer' : {
                    question_id : '1', 
                    question_text : 'Testing one scenario for questionnaire. *',
                    gui_control : 'radio', 
                    options: ['Yes','No'], 
                    answer_max : 1, 
                    answer_min : 1
                }
            }
        ]
    }]
);

I hope this helps to get you moving forward!

Also, I wanted to lastly point out that this is definitely not an efficient data model having nested User Defined Types (UDT), but thats for a different day's discussion. I would strongly encourage you to view the below resources to understand Cassandra data modeling in general,

• Data Modeling by Example
• Cassandra Fundamentals
• Inserting collection types into C* table:
  • Set
  • List
  • Map
  • UDT