Delete Valuator query

Select * from fvalue."Documents" where "DocumentUniqueId"='NSD_000444'

Select * from fvalue."Contract" where "DocumentId"=444

Select * from fvalue."ContractVersions" where "ContractId"=347

Select * from fvalue."DocumentRelationship" where "RelatedDocumentId"=444

Select * from fvalue."DocumentSection" where "DocumentSectionId"=936

Select * from fvalue."section_category_and_contact_details" where "DocumentSectionId"=731

Select * from fvalue."section_valuator_company_details" where "DocumentSectionId"=732

select * from fvalue."section_address" where "DocumentSectionId"=733

Select * from fvalue."section_working_area" where "DocumentSectionId"=734

Better Approach 

DO $$
DECLARE
    v_document_id INT;
    v_contract_id INT;
    r RECORD;
BEGIN
    -- Get DocumentId
    SELECT "DocumentId"
    INTO v_document_id
    FROM fvalue."Documents"
    WHERE "DocumentUniqueId" = 'NSD_000554';

    IF v_document_id IS NULL THEN
        RAISE EXCEPTION 'Document not found.';
    END IF;

    -- Get ContractId
    SELECT "ContractId"
    INTO v_contract_id
    FROM fvalue."Contract"
    WHERE "DocumentId" = v_document_id;

    ------------------------------------------------------------------
    -- Delete every section_* table automatically
    ------------------------------------------------------------------
    FOR r IN
        SELECT tc.table_name
        FROM information_schema.table_constraints tc
        JOIN information_schema.key_column_usage kcu
            ON tc.constraint_name = kcu.constraint_name
        JOIN information_schema.constraint_column_usage ccu
            ON ccu.constraint_name = tc.constraint_name
        WHERE tc.constraint_type = 'FOREIGN KEY'
          AND tc.table_schema = 'fvalue'
          AND ccu.table_name = 'DocumentSection'
    LOOP
        EXECUTE format(
            'DELETE FROM fvalue.%I
             WHERE "DocumentSectionId" IN
             (
                 SELECT "DocumentSectionId"
                 FROM fvalue."DocumentSection"
                 WHERE "DocumentId" = $1
             )',
            r.table_name
        ) USING v_document_id;
    END LOOP;

    ------------------------------------------------------------------
    -- Delete DocumentSection
    ------------------------------------------------------------------
    DELETE FROM fvalue."DocumentSection"
    WHERE "DocumentId" = v_document_id;

    ------------------------------------------------------------------
    -- Delete ContractVersions
    ------------------------------------------------------------------
    DELETE FROM fvalue."ContractVersions"
    WHERE "ContractId" = v_contract_id
       OR "DocumentId" = v_document_id;

    ------------------------------------------------------------------
    -- Delete Contract
    ------------------------------------------------------------------
    DELETE FROM fvalue."Contract"
    WHERE "DocumentId" = v_document_id;

    ------------------------------------------------------------------
    -- Delete Relationships
    ------------------------------------------------------------------
    DELETE FROM fvalue."DocumentRelationship"
    WHERE "DocumentId" = v_document_id
       OR "RelatedDocumentId" = v_document_id;

    ------------------------------------------------------------------
    -- Delete Document
    ------------------------------------------------------------------
    DELETE FROM fvalue."Documents"
    WHERE "DocumentId" = v_document_id;

    RAISE NOTICE 'Document % deleted successfully.', v_document_id;

END $$;