0040_auto_20221122_0613.py

# Generated by Django 4.1.1 on 2022-11-22 06:13

from django.db import migrations, connection, transaction


def populate_concept_id_in_localized_texts(apps, schema_editor):
    import time
    start = time.time()
    """
    1. Populates concept_id in localized_texts table using concepts_names (many-to-many).
    2. After this migration:
       - localized_texts table will have concept_id for each name
       - localized_texts without any concept_id can be deleted, as they are all descriptions which were migrated earlier
       - count of concepts_names (old) should equal to count of localized_texts with concept_id
    """
    def get_statement():
        return "update localized_texts as l set concept_id = n.concept_id from (values"
    with connection.cursor() as cursor:
        cursor.execute("select concept_id, localizedtext_id from concepts_names;")
        names = cursor.fetchall()
        statement = get_statement()
        count = 0
        for name in names:
            statement += f'{name},'
            count += 1
            if count == 10000:
                if statement.endswith(','):
                    statement = statement[:-1]
                print("Updating 10000...")
                statement += ') as n(concept_id, localizedtext_id) where n.localizedtext_id = l.id;'
                cursor.execute(statement)
                statement = get_statement()
                count = 0

        if count > 0:
            if statement.endswith(','):
                statement = statement[:-1]
            statement += ') as n(concept_id, localizedtext_id) where n.localizedtext_id = l.id;'
            print(f"Updating last {count}...")
            cursor.execute(statement)

    print('Time: ', time.time() - start)


class Migration(migrations.Migration):
    atomic = False

    dependencies = [
        ('concepts', '0039_auto_20221122_0552'),
    ]

    operations = [
        migrations.RunPython(populate_concept_id_in_localized_texts)
    ]