| from django.db.backends import BaseDatabaseValidation |
| |
| class DatabaseValidation(BaseDatabaseValidation): |
| def validate_field(self, errors, opts, f): |
| """ |
| There are some field length restrictions for MySQL: |
| |
| - Prior to version 5.0.3, character fields could not exceed 255 |
| characters in length. |
| - No character (varchar) fields can have a length exceeding 255 |
| characters if they have a unique index on them. |
| """ |
| from django.db import models |
| db_version = self.connection.get_server_version() |
| varchar_fields = (models.CharField, models.CommaSeparatedIntegerField, |
| models.SlugField) |
| if isinstance(f, varchar_fields) and f.max_length > 255: |
| if db_version < (5, 0, 3): |
| msg = '"%(name)s": %(cls)s cannot have a "max_length" greater than 255 when you are using a version of MySQL prior to 5.0.3 (you are using %(version)s).' |
| elif f.unique == True: |
| msg = '"%(name)s": %(cls)s cannot have a "max_length" greater than 255 when using "unique=True".' |
| else: |
| msg = None |
| |
| if msg: |
| errors.add(opts, msg % {'name': f.name, 'cls': f.__class__.__name__, 'version': '.'.join([str(n) for n in db_version[:3]])}) |
