+
+def _setup_tablespace_sql(config):
+ """ Returns a dict with tablespace expressions for the different tablespace
+ kinds depending on whether a tablespace is configured or not.
+ """
+ out = {}
+ for subset in ('ADDRESS', 'SEARCH', 'AUX'):
+ for kind in ('DATA', 'INDEX'):
+ tspace = getattr(config, 'TABLESPACE_{}_{}'.format(subset, kind))
+ if tspace:
+ tspace = 'TABLESPACE "{}"'.format(tspace)
+ out['{}_{}'.format(subset.lower, kind.lower())] = tspace
+
+ return out
+
+
+def _setup_postgres_sql(conn):
+ """ Set up a dictionary with various Postgresql/Postgis SQL terms which
+ are dependent on the database version in use.
+ """
+ out = {}
+ pg_version = conn.server_version_tuple()
+ # CREATE INDEX IF NOT EXISTS was introduced in PG9.5.
+ # Note that you need to ignore failures on older versions when
+ # using this construct.
+ out['if_index_not_exists'] = ' IF NOT EXISTS ' if pg_version >= (9, 5, 0) else ''
+
+ return out
+
+
+def _setup_postgresql_features(conn):
+ """ Set up a dictionary with various optional Postgresql/Postgis features that
+ depend on the database version.
+ """
+ pg_version = conn.server_version_tuple()
+ return {
+ 'has_index_non_key_column' : pg_version >= (11, 0, 0)
+ }
+
+class SQLPreprocessor: