[Answer]-Django foreign key in model

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The best way is to have symbol field as the foreign key to Sttlmnt_typ_Master.

But if you sure want models like this then add this method to you ModelAdmin:

class AuctionAdmin(admin.ModelAdmin):
    list_display = ('dates', 'sr_no', 'symbol_display', 'series', 'qty')

    def symbol_display(self, obj):
        symbol = Sttlmnt_typ_Master.objects.filter(symbol=obj.symbol).first()
        return symbol.symbol_name if symbol else obj.symbol
    symbol_display.short_description = 'Symbol'

This will work but filtering Sttlmnt_typ_Master for every row in admin is very inefficient. You should consider to switch to “foreign key” option.

EDIT: Foreign key option.

Add the __unicode__ method to Sttlmnt_typ_Master model and change Auction.symbol field to ForeignKey:

class Sttlmnt_typ_Master(models.Model): 
    symbol = models.CharField(max_length=10, editable=False)
    symbol_name =  models.CharField(max_length=35, editable=False)

    def __unicode__(self):
        return self.symbol_name

class Auction(models.Model):
    dates = models.DateTimeField(editable=False, null=True)
    sr_no = models.IntegerField(editable=False, null=True)
    symbol = models.ForeignKey(Sttlmnt_typ_Master, editable=False)
    series = models.CharField(max_length=35, editable=False, null=True)
    qty = models.IntegerField(editable=False, null=True)

Now changelist in admin will display symbol field with symbol_name property. Django admin is smart enough to add select_related('symbol') to queryset so there will be no additional queries to database.

Of course you should change your import function to populate Auction.symbol fields with valid Sttlmnt_typ_Master instances instead of plain text.

EDIT2: Populating Auction.symbol field.

symbol = 'ZYDUSWELL'
auction.symbol, created = Sttlmnt_typ_Master.objects.get_or_create(
                             symbol=symbol, defaults={'symbol_name': symbol})

See the documentation.

👤catavaran

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