fix: Unique and Index constraints

frappe/database/mariadb/schema.py

@@ -62,7 +62,7 @@ class MariaDBTable(DBTable):
 			if not frappe.db.has_index(self.table_name, col.fieldname + '_index'):
 				add_index_query.append("ADD INDEX `{}_index`(`{}`)".format(col.fieldname, col.fieldname))
 
-		for col in self.drop_index:
+		for col in self.drop_index + self.drop_unique:
 			if col.fieldname != 'name': # primary key
 				current_column = self.current_columns.get(col.fieldname.lower())
 				unique_constraint_changed = current_column.unique != col.unique

frappe/database/postgres/database.py

@@ -77,11 +77,11 @@ class PostgresDatabase(Database):
 		"""Escape quotes and percent in given string."""
 		if isinstance(s, bytes):
 			s = s.decode('utf-8')
-				
+
 		# MariaDB's driver treats None as an empty string
 		# So Postgres should do the same
 
-		if s is None: 
+		if s is None:
 			s = ''
 
 		if percent:
@@ -308,18 +308,20 @@ class PostgresDatabase(Database):
 				WHEN 'timestamp without time zone' THEN 'timestamp'
 				ELSE a.data_type
 			END AS type,
-			COUNT(b.indexdef) AS Index,
+			BOOL_OR(b.index) AS index,
 			SPLIT_PART(COALESCE(a.column_default, NULL), '::', 1) AS default,
 			BOOL_OR(b.unique) AS unique
 			FROM information_schema.columns a
 			LEFT JOIN
-				(SELECT indexdef, tablename, indexdef LIKE '%UNIQUE INDEX%' AS unique
+				(SELECT indexdef, tablename,
+					indexdef LIKE '%UNIQUE INDEX%' AS unique,
+					indexdef NOT LIKE '%UNIQUE INDEX%' AS index
 					FROM pg_indexes
 					WHERE tablename='{table_name}') b
-					ON SUBSTRING(b.indexdef, '\(.*\)') LIKE CONCAT('%', a.column_name, '%')
+				ON SUBSTRING(b.indexdef, '\(.*\)') LIKE CONCAT('%', a.column_name, '%')
 			WHERE a.table_name = '{table_name}'
-			GROUP BY a.column_name, a.data_type, a.column_default, a.character_maximum_length;'''
-			.format(table_name=table_name), as_dict=1)
+			GROUP BY a.column_name, a.data_type, a.column_default, a.character_maximum_length;
+		'''.format(table_name=table_name), as_dict=1)
 
 	def get_database_list(self, target):
 		return [d[0] for d in self.sql("SELECT datname FROM pg_database;")]

frappe/database/postgres/schema.py

@@ -52,8 +52,8 @@ class PostgresTable(DBTable):
 			query.append("ALTER COLUMN `{0}` TYPE {1} {2}".format(
 				col.fieldname,
 				get_definition(col.fieldtype, precision=col.precision, length=col.length),
-				using_clause)
-			)
+				using_clause
+			))
 
 		for col in self.set_default:
 			if col.fieldname=="name":
@@ -73,37 +73,49 @@ class PostgresTable(DBTable):
 
 			query.append("ALTER COLUMN `{}` SET DEFAULT {}".format(col.fieldname, col_default))
 
-		create_index_query = ""
+		create_contraint_query = ""
 		for col in self.add_index:
 			# if index key not exists
-			create_index_query += 'CREATE INDEX IF NOT EXISTS "{index_name}" ON `{table_name}`(`{field}`);'.format(
+			create_contraint_query += 'CREATE INDEX IF NOT EXISTS "{index_name}" ON `{table_name}`(`{field}`);'.format(
 				index_name=col.fieldname,
 				table_name=self.table_name,
 				field=col.fieldname)
 
-		drop_index_query = ""
+		for col in self.add_unique:
+			# if index key not exists
+			create_contraint_query += 'CREATE UNIQUE INDEX IF NOT EXISTS "unique_{index_name}" ON `{table_name}`(`{field}`);'.format(
+				index_name=col.fieldname,
+				table_name=self.table_name,
+				field=col.fieldname
+			)
+
+		drop_contraint_query = ""
 		for col in self.drop_index:
 			# primary key
 			if col.fieldname != 'name':
 				# if index key exists
-				if not frappe.db.has_index(self.table_name, col.fieldname):
-					drop_index_query += 'DROP INDEX IF EXISTS "{}" ;'.format(col.fieldname)
+				drop_contraint_query += 'DROP INDEX IF EXISTS "{}" ;'.format(col.fieldname)
 
-		if query:
-			try:
+		for col in self.drop_unique:
+			# primary key
+			if col.fieldname != 'name':
+				# if index key exists
+				drop_contraint_query += 'DROP INDEX IF EXISTS "unique_{}" ;'.format(col.fieldname)
+		try:
+			if query:
 				final_alter_query = "ALTER TABLE `{}` {}".format(self.table_name, ", ".join(query))
 				if final_alter_query: frappe.db.sql(final_alter_query)
-				if create_index_query: frappe.db.sql(create_index_query)
-				if drop_index_query: frappe.db.sql(drop_index_query)
-			except Exception as e:
-				# sanitize
-				if frappe.db.is_duplicate_fieldname(e):
-					frappe.throw(str(e))
-				elif frappe.db.is_duplicate_entry(e):
-					fieldname = str(e).split("'")[-2]
-					frappe.throw(_("""{0} field cannot be set as unique in {1},
-						as there are non-unique existing values""".format(
-						fieldname, self.table_name)))
-					raise e
-				else:
-					raise e
+			if create_contraint_query: frappe.db.sql(create_contraint_query)
+			if drop_contraint_query: frappe.db.sql(drop_contraint_query)
+		except Exception as e:
+			# sanitize
+			if frappe.db.is_duplicate_fieldname(e):
+				frappe.throw(str(e))
+			elif frappe.db.is_duplicate_entry(e):
+				fieldname = str(e).split("'")[-2]
+				frappe.throw(_("""{0} field cannot be set as unique in {1},
+					as there are non-unique existing values""".format(
+					fieldname, self.table_name)))
+				raise e
+			else:
+				raise e

frappe/database/schema.py

@@ -21,6 +21,7 @@ class DBTable:
 		self.change_name = []
 		self.add_unique = []
 		self.add_index = []
+		self.drop_unique = []
 		self.drop_index = []
 		self.set_default = []
 
@@ -219,8 +220,10 @@ class DbColumn:
 			self.table.change_type.append(self)
 
 		# unique
-		if((self.unique and not current_def['unique']) and column_type not in ('text', 'longtext')):
+		if ((self.unique and not current_def['unique']) and column_type not in ('text', 'longtext')):
 			self.table.add_unique.append(self)
+		elif (current_def['unique'] and not self.unique):
+			self.table.drop_unique.append(self)
 
 		# default
 		if (self.default_changed(current_def)
@@ -230,9 +233,7 @@ class DbColumn:
 			self.table.set_default.append(self)
 
 		# index should be applied or dropped irrespective of type change
-		if ((current_def['index'] and not self.set_index)
-			or (current_def['unique'] and not self.unique)):
-			# to drop unique you have to drop index
+		if (current_def['index'] and not self.set_index):
 			self.table.drop_index.append(self)
 
 		elif (not current_def['index'] and self.set_index) and not (column_type in ('text', 'longtext')):