diff options
Diffstat (limited to 'lib/sqlalchemy/dialects/postgresql/base.py')
| -rw-r--r-- | lib/sqlalchemy/dialects/postgresql/base.py | 52 |
1 files changed, 40 insertions, 12 deletions
diff --git a/lib/sqlalchemy/dialects/postgresql/base.py b/lib/sqlalchemy/dialects/postgresql/base.py index 556493b3c..baa640eaa 100644 --- a/lib/sqlalchemy/dialects/postgresql/base.py +++ b/lib/sqlalchemy/dialects/postgresql/base.py @@ -402,6 +402,28 @@ underlying CREATE INDEX command, so it *must* be a valid index type for your version of PostgreSQL. +.. _postgresql_index_reflection: + +Postgresql Index Reflection +--------------------------- + +The Postgresql database creates a UNIQUE INDEX implicitly whenever the +UNIQUE CONSTRAINT construct is used. When inspecting a table using +:class:`.Inspector`, the :meth:`.Inspector.get_indexes` +and the :meth:`.Inspector.get_unique_constraints` will report on these +two constructs distinctly; in the case of the index, the key +``duplicates_constraint`` will be present in the index entry if it is +detected as mirroring a constraint. When performing reflection using +``Table(..., autoload=True)``, the UNIQUE INDEX is **not** returned +in :attr:`.Table.indexes` when it is detected as mirroring a +:class:`.UniqueConstraint` in the :attr:`.Table.constraints` collection. + +.. versionchanged:: 1.0.0 - :class:`.Table` reflection now includes + :class:`.UniqueConstraint` objects present in the :attr:`.Table.constraints` + collection; the Postgresql backend will no longer include a "mirrored" + :class:`.Index` construct in :attr:`.Table.indexes` if it is detected + as corresponding to a unique constraint. + Special Reflection Options -------------------------- @@ -2523,21 +2545,27 @@ class PGDialect(default.DefaultDialect): % idx_name) sv_idx_name = idx_name + has_idx = idx_name in indexes index = indexes[idx_name] if col is not None: index['cols'][col_num] = col - index['key'] = [int(k.strip()) for k in idx_key.split()] - index['unique'] = unique - index['duplicates_constraint'] = (None if conrelid is None - else idx_name) - - return [ - {'name': name, - 'unique': idx['unique'], - 'column_names': [idx['cols'][i] for i in idx['key']], - 'duplicates_constraint': idx['duplicates_constraint']} - for name, idx in indexes.items() - ] + if not has_idx: + index['key'] = [int(k.strip()) for k in idx_key.split()] + index['unique'] = unique + if conrelid is not None: + index['duplicates_constraint'] = idx_name + + result = [] + for name, idx in indexes.items(): + entry = { + 'name': name, + 'unique': idx['unique'], + 'column_names': [idx['cols'][i] for i in idx['key']] + } + if 'duplicates_constraint' in idx: + entry['duplicates_constraint'] = idx['duplicates_constraint'] + result.append(entry) + return result @reflection.cache def get_unique_constraints(self, connection, table_name, |