diff -r 57b4279d8c4e -r 03e267d67478 app/django/db/backends/mysql_old/introspection.py --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/app/django/db/backends/mysql_old/introspection.py Fri Jul 18 18:22:23 2008 +0000 @@ -0,0 +1,96 @@ +from django.db.backends.mysql_old.base import DatabaseOperations +from MySQLdb import ProgrammingError, OperationalError +from MySQLdb.constants import FIELD_TYPE +import re + +quote_name = DatabaseOperations().quote_name +foreign_key_re = re.compile(r"\sCONSTRAINT `[^`]*` FOREIGN KEY \(`([^`]*)`\) REFERENCES `([^`]*)` \(`([^`]*)`\)") + +def get_table_list(cursor): + "Returns a list of table names in the current database." + cursor.execute("SHOW TABLES") + return [row[0] for row in cursor.fetchall()] + +def get_table_description(cursor, table_name): + "Returns a description of the table, with the DB-API cursor.description interface." + cursor.execute("SELECT * FROM %s LIMIT 1" % quote_name(table_name)) + return cursor.description + +def _name_to_index(cursor, table_name): + """ + Returns a dictionary of {field_name: field_index} for the given table. + Indexes are 0-based. + """ + return dict([(d[0], i) for i, d in enumerate(get_table_description(cursor, table_name))]) + +def get_relations(cursor, table_name): + """ + Returns a dictionary of {field_index: (field_index_other_table, other_table)} + representing all relationships to the given table. Indexes are 0-based. + """ + my_field_dict = _name_to_index(cursor, table_name) + constraints = [] + relations = {} + try: + # This should work for MySQL 5.0. + cursor.execute(""" + SELECT column_name, referenced_table_name, referenced_column_name + FROM information_schema.key_column_usage + WHERE table_name = %s + AND table_schema = DATABASE() + AND referenced_table_name IS NOT NULL + AND referenced_column_name IS NOT NULL""", [table_name]) + constraints.extend(cursor.fetchall()) + except (ProgrammingError, OperationalError): + # Fall back to "SHOW CREATE TABLE", for previous MySQL versions. + # Go through all constraints and save the equal matches. + cursor.execute("SHOW CREATE TABLE %s" % quote_name(table_name)) + for row in cursor.fetchall(): + pos = 0 + while True: + match = foreign_key_re.search(row[1], pos) + if match == None: + break + pos = match.end() + constraints.append(match.groups()) + + for my_fieldname, other_table, other_field in constraints: + other_field_index = _name_to_index(cursor, other_table)[other_field] + my_field_index = my_field_dict[my_fieldname] + relations[my_field_index] = (other_field_index, other_table) + + return relations + +def get_indexes(cursor, table_name): + """ + Returns a dictionary of fieldname -> infodict for the given table, + where each infodict is in the format: + {'primary_key': boolean representing whether it's the primary key, + 'unique': boolean representing whether it's a unique index} + """ + cursor.execute("SHOW INDEX FROM %s" % quote_name(table_name)) + indexes = {} + for row in cursor.fetchall(): + indexes[row[4]] = {'primary_key': (row[2] == 'PRIMARY'), 'unique': not bool(row[1])} + return indexes + +DATA_TYPES_REVERSE = { + FIELD_TYPE.BLOB: 'TextField', + FIELD_TYPE.CHAR: 'CharField', + FIELD_TYPE.DECIMAL: 'DecimalField', + FIELD_TYPE.DATE: 'DateField', + FIELD_TYPE.DATETIME: 'DateTimeField', + FIELD_TYPE.DOUBLE: 'FloatField', + FIELD_TYPE.FLOAT: 'FloatField', + FIELD_TYPE.INT24: 'IntegerField', + FIELD_TYPE.LONG: 'IntegerField', + FIELD_TYPE.LONGLONG: 'IntegerField', + FIELD_TYPE.SHORT: 'IntegerField', + FIELD_TYPE.STRING: 'TextField', + FIELD_TYPE.TIMESTAMP: 'DateTimeField', + FIELD_TYPE.TINY: 'IntegerField', + FIELD_TYPE.TINY_BLOB: 'TextField', + FIELD_TYPE.MEDIUM_BLOB: 'TextField', + FIELD_TYPE.LONG_BLOB: 'TextField', + FIELD_TYPE.VAR_STRING: 'CharField', +}