| from django.db.backends import BaseDatabaseIntrospection |
| import cx_Oracle |
| import re |
| |
| foreign_key_re = re.compile(r"\sCONSTRAINT `[^`]*` FOREIGN KEY \(`([^`]*)`\) REFERENCES `([^`]*)` \(`([^`]*)`\)") |
| |
| class DatabaseIntrospection(BaseDatabaseIntrospection): |
| # Maps type objects to Django Field types. |
| data_types_reverse = { |
| cx_Oracle.CLOB: 'TextField', |
| cx_Oracle.DATETIME: 'DateTimeField', |
| cx_Oracle.FIXED_CHAR: 'CharField', |
| cx_Oracle.NCLOB: 'TextField', |
| cx_Oracle.NUMBER: 'DecimalField', |
| cx_Oracle.STRING: 'CharField', |
| cx_Oracle.TIMESTAMP: 'DateTimeField', |
| } |
| |
| def get_table_list(self, cursor): |
| "Returns a list of table names in the current database." |
| cursor.execute("SELECT TABLE_NAME FROM USER_TABLES") |
| return [row[0].upper() for row in cursor.fetchall()] |
| |
| def get_table_description(self, cursor, table_name): |
| "Returns a description of the table, with the DB-API cursor.description interface." |
| cursor.execute("SELECT * FROM %s WHERE ROWNUM < 2" % self.connection.ops.quote_name(table_name)) |
| return cursor.description |
| |
| def table_name_converter(self, name): |
| "Table name comparison is case insensitive under Oracle" |
| return name.upper() |
| |
| def _name_to_index(self, 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(self.get_table_description(cursor, table_name))]) |
| |
| def get_relations(self, 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. |
| """ |
| cursor.execute(""" |
| SELECT ta.column_id - 1, tb.table_name, tb.column_id - 1 |
| FROM user_constraints, USER_CONS_COLUMNS ca, USER_CONS_COLUMNS cb, |
| user_tab_cols ta, user_tab_cols tb |
| WHERE user_constraints.table_name = %s AND |
| ta.table_name = %s AND |
| ta.column_name = ca.column_name AND |
| ca.table_name = %s AND |
| user_constraints.constraint_name = ca.constraint_name AND |
| user_constraints.r_constraint_name = cb.constraint_name AND |
| cb.table_name = tb.table_name AND |
| cb.column_name = tb.column_name AND |
| ca.position = cb.position""", [table_name, table_name, table_name]) |
| |
| relations = {} |
| for row in cursor.fetchall(): |
| relations[row[0]] = (row[2], row[1]) |
| return relations |
| |
| def get_indexes(self, 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} |
| """ |
| # This query retrieves each index on the given table, including the |
| # first associated field name |
| # "We were in the nick of time; you were in great peril!" |
| sql = """ |
| WITH primarycols AS ( |
| SELECT user_cons_columns.table_name, user_cons_columns.column_name, 1 AS PRIMARYCOL |
| FROM user_cons_columns, user_constraints |
| WHERE user_cons_columns.constraint_name = user_constraints.constraint_name AND |
| user_constraints.constraint_type = 'P' AND |
| user_cons_columns.table_name = %s), |
| uniquecols AS ( |
| SELECT user_ind_columns.table_name, user_ind_columns.column_name, 1 AS UNIQUECOL |
| FROM user_indexes, user_ind_columns |
| WHERE uniqueness = 'UNIQUE' AND |
| user_indexes.index_name = user_ind_columns.index_name AND |
| user_ind_columns.table_name = %s) |
| SELECT allcols.column_name, primarycols.primarycol, uniquecols.UNIQUECOL |
| FROM (SELECT column_name FROM primarycols UNION SELECT column_name FROM |
| uniquecols) allcols, |
| primarycols, uniquecols |
| WHERE allcols.column_name = primarycols.column_name (+) AND |
| allcols.column_name = uniquecols.column_name (+) |
| """ |
| cursor.execute(sql, [table_name, table_name]) |
| indexes = {} |
| for row in cursor.fetchall(): |
| # row[1] (idx.indkey) is stored in the DB as an array. It comes out as |
| # a string of space-separated integers. This designates the field |
| # indexes (1-based) of the fields that have indexes on the table. |
| # Here, we skip any indexes across multiple fields. |
| indexes[row[0]] = {'primary_key': row[1], 'unique': row[2]} |
| return indexes |
| |