Adust the as_table tag to render a pick link if appropriate
The templates are adjusted to pass on a 'reference' value, which
is the url_name of the view from which the entity should be picked.
The as_table (and related) function(s) construct and then pass on
this argument and enable takes_contex so that we have access to the
context of the enclosing template.
We only extract ReferenceProperties that end with '_link_id' since
that is how all RP's are currently named. It is not possible to
create a field with the same name as the RP, as GAE will try to
interpret it's contents as the key of an entity before even calling
any function we can override.
Patch by: Sverre Rabbelier
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