from django.db import models

class Book(models.Model):

    title = models.CharField(max_length=50)

    author = models.CharField(max_length=50)

    pages = models.IntegerField(db_column="page_count")

    shortcut = models.CharField(max_length=50, db_tablespace="idx_tbls")

    isbn = models.CharField(max_length=50, db_tablespace="idx_tbls")

    barcode = models.CharField(max_length=31)

    class Meta:

        indexes = [

            models.Index(fields=["title"]),

            models.Index(fields=["isbn", "id"]),

            models.Index(

                fields=["barcode"], name="%(app_label)s_%(class)s_barcode_idx"

            ),

        ]

class AbstractModel(models.Model):

    name = models.CharField(max_length=50)

    shortcut = models.CharField(max_length=3)

    class Meta:

        abstract = True

        indexes = [

            models.Index(fields=["name"]),

            models.Index(fields=["shortcut"], name="%(app_label)s_%(class)s_idx"),

        ]

class ChildModel1(AbstractModel):

    pass

class ChildModel2(AbstractModel):

    pass