For PostgreSQL, create 1k rows with 10k of random text each

insert.sql

WITH RECURSIVE random_chars AS (
    SELECT 
        1 AS id, 
        1 AS group_id,
        substr(
            'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789',
            floor(random() * 62)::int + 1,
            1
        ) AS char

    UNION ALL

    SELECT 
        CASE 
            WHEN id < 10000 THEN id + 1 
            ELSE 1 
        END AS id,
        CASE 
            WHEN id < 10000 THEN group_id 
            ELSE group_id + 1 
        END AS group_id,
        substr(
            'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789',
            floor(random() * 62)::int + 1,
            1
        )
    FROM random_chars
    WHERE group_id < 1000
),
aggregated_chars AS (
    SELECT 
        group_id, 
        string_agg(char, '') AS random_string
    FROM random_chars
    GROUP BY group_id
)
INSERT INTO orbeon_form_data 
    (form_version, deleted, draft, 
    xml)
SELECT 
    1, 'N', 'N',
    ('<_>' || random_string || '</_>')::xml
FROM aggregated_chars;