Mercurial > kallithea

comparison rhodecode/lib/dbmigrate/migrate/changeset/databases/oracle.py @ 833:9753e0907827 beta

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
added dbmigrate package, added model changes moved out upgrade db command to that package
author Marcin Kuzminski <marcin@python-works.com>
date Sat, 11 Dec 2010 01:54:12 +0100
parents
children 08d2dcd71666
comparison
equal deleted inserted replaced
832:634596f81cfd 833:9753e0907827
1 """
2 Oracle database specific implementations of changeset classes.
3 """
4 import sqlalchemy as sa
5 from sqlalchemy.databases import oracle as sa_base
6
7 from migrate import exceptions
8 from migrate.changeset import ansisql, SQLA_06
9
10
11 if not SQLA_06:
12 OracleSchemaGenerator = sa_base.OracleSchemaGenerator
13 else:
14 OracleSchemaGenerator = sa_base.OracleDDLCompiler
15
16
17 class OracleColumnGenerator(OracleSchemaGenerator, ansisql.ANSIColumnGenerator):
18 pass
19
20
21 class OracleColumnDropper(ansisql.ANSIColumnDropper):
22 pass
23
24
25 class OracleSchemaChanger(OracleSchemaGenerator, ansisql.ANSISchemaChanger):
26
27 def get_column_specification(self, column, **kwargs):
28 # Ignore the NOT NULL generated
29 override_nullable = kwargs.pop('override_nullable', None)
30 if override_nullable:
31 orig = column.nullable
32 column.nullable = True
33 ret = super(OracleSchemaChanger, self).get_column_specification(
34 column, **kwargs)
35 if override_nullable:
36 column.nullable = orig
37 return ret
38
39 def visit_column(self, delta):
40 keys = delta.keys()
41
42 if 'name' in keys:
43 self._run_subvisit(delta,
44 self._visit_column_name,
45 start_alter=False)
46
47 if len(set(('type', 'nullable', 'server_default')).intersection(keys)):
48 self._run_subvisit(delta,
49 self._visit_column_change,
50 start_alter=False)
51
52 def _visit_column_change(self, table, column, delta):
53 # Oracle cannot drop a default once created, but it can set it
54 # to null. We'll do that if default=None
55 # http://forums.oracle.com/forums/message.jspa?messageID=1273234#1273234
56 dropdefault_hack = (column.server_default is None \
57 and 'server_default' in delta.keys())
58 # Oracle apparently doesn't like it when we say "not null" if
59 # the column's already not null. Fudge it, so we don't need a
60 # new function
61 notnull_hack = ((not column.nullable) \
62 and ('nullable' not in delta.keys()))
63 # We need to specify NULL if we're removing a NOT NULL
64 # constraint
65 null_hack = (column.nullable and ('nullable' in delta.keys()))
66
67 if dropdefault_hack:
68 column.server_default = sa.PassiveDefault(sa.sql.null())
69 if notnull_hack:
70 column.nullable = True
71 colspec = self.get_column_specification(column,
72 override_nullable=null_hack)
73 if null_hack:
74 colspec += ' NULL'
75 if notnull_hack:
76 column.nullable = False
77 if dropdefault_hack:
78 column.server_default = None
79
80 self.start_alter_table(table)
81 self.append("MODIFY (")
82 self.append(colspec)
83 self.append(")")
84
85
86 class OracleConstraintCommon(object):
87
88 def get_constraint_name(self, cons):
89 # Oracle constraints can't guess their name like other DBs
90 if not cons.name:
91 raise exceptions.NotSupportedError(
92 "Oracle constraint names must be explicitly stated")
93 return cons.name
94
95
96 class OracleConstraintGenerator(OracleConstraintCommon,
97 ansisql.ANSIConstraintGenerator):
98 pass
99
100
101 class OracleConstraintDropper(OracleConstraintCommon,
102 ansisql.ANSIConstraintDropper):
103 pass
104
105
106 class OracleDialect(ansisql.ANSIDialect):
107 columngenerator = OracleColumnGenerator
108 columndropper = OracleColumnDropper
109 schemachanger = OracleSchemaChanger
110 constraintgenerator = OracleConstraintGenerator
111 constraintdropper = OracleConstraintDropper