Merge branch 'develop' of https://github.com/Infinidat/infi.clickhouse_orm into develop

CHANGELOG.rst

@@ -1,11 +1,13 @@
 Change Log
 ==========
 
-Unreleased
-----------
+v0.8.1
+------
 - Add support for ReplacingMergeTree (leenr)
 - Fix problem with SELECT WITH TOTALS (pilosus)
 - Update serialization format of DateTimeField to 10 digits, zero padded (nikepan)
+- Greatly improve performance when inserting large strings (credit to M1hacka for identifying the problem)
+- Reduce memory footprint of Database.insert()
 
 v0.8.0
 ------

src/infi/clickhouse_orm/database.py

@@ -50,6 +50,7 @@ class Database(object):
 
     def insert(self, model_instances, batch_size=1000):
         from six import next
+        from cStringIO import StringIO
         i = iter(model_instances)
         try:
             first_instance = next(i)
@@ -61,22 +62,27 @@ class Database(object):
             raise DatabaseException("You can't insert into read only table")
 
         def gen():
-            yield self._substitute('INSERT INTO $table FORMAT TabSeparated\n', model_class).encode('utf-8')
+            buf = StringIO()
+            buf.write(self._substitute('INSERT INTO $table FORMAT TabSeparated\n', model_class).encode('utf-8'))
             first_instance.set_database(self)
-            yield (first_instance.to_tsv(include_readonly=False) + '\n').encode('utf-8')
+            buf.write(first_instance.to_tsv(include_readonly=False).encode('utf-8'))
+            buf.write('\n')
             # Collect lines in batches of batch_size
-            batch = []
+            lines = 2
             for instance in i:
                 instance.set_database(self)
-                batch.append(instance.to_tsv(include_readonly=False))
-                if len(batch) >= batch_size:
+                buf.write(instance.to_tsv(include_readonly=False).encode('utf-8'))
+                buf.write('\n')
+                lines += 1
+                if lines >= batch_size:
                     # Return the current batch of lines
-                    yield ('\n'.join(batch) + '\n').encode('utf-8')
+                    yield buf.getvalue()
                     # Start a new batch
-                    batch = []
+                    buf = StringIO()
+                    lines = 0
             # Return any remaining lines in partial batch
-            if batch:
-                yield ('\n'.join(batch) + '\n').encode('utf-8')
+            if lines:
+                yield buf.getvalue()
         self._send(gen())
 
     def count(self, model_class, conditions=None):

src/infi/clickhouse_orm/fields.py

@@ -154,6 +154,11 @@ class BaseIntField(Field):
         except:
             raise ValueError('Invalid value for %s - %r' % (self.__class__.__name__, value))
 
+    def to_db_string(self, value, quote=True):
+        # There's no need to call escape since numbers do not contain 
+        # special characters, and never need quoting
+        return text_type(value)
+
     def validate(self, value):
         self._range_check(value, self.min_value, self.max_value)
 
@@ -222,6 +227,11 @@ class BaseFloatField(Field):
         except:
             raise ValueError('Invalid value for %s - %r' % (self.__class__.__name__, value))
 
+    def to_db_string(self, value, quote=True):
+        # There's no need to call escape since numbers do not contain 
+        # special characters, and never need quoting
+        return text_type(value)
+
 
 class Float32Field(BaseFloatField):
 

src/infi/clickhouse_orm/models.py

@@ -27,6 +27,7 @@ class ModelBase(type):
         fields = base_fields + [item for item in attrs.items() if isinstance(item[1], Field)]
         fields.sort(key=lambda item: item[1].creation_counter)
         setattr(new_cls, '_fields', fields)
+        setattr(new_cls, '_writable_fields', [f for f in fields if not f[1].readonly])
         return new_cls
 
     @classmethod
@@ -186,7 +187,7 @@ class Model(with_metaclass(ModelBase)):
         :param bool include_readonly: If False, returns only fields, that can be inserted into database
         '''
         data = self.__dict__
-        fields = self._fields if include_readonly else [f for f in self._fields if not f[1].readonly]
+        fields = self._fields if include_readonly else self._writable_fields
         return '\t'.join(field.to_db_string(data[name], quote=False) for name, field in fields)
 
     def to_dict(self, include_readonly=True, field_names=None):
@@ -195,7 +196,7 @@ class Model(with_metaclass(ModelBase)):
         :param bool include_readonly: If False, returns only fields, that can be inserted into database
         :param field_names: An iterable of field names to return
         '''
-        fields = self._fields if include_readonly else [f for f in self._fields if not f[1].readonly]
+        fields = self._fields if include_readonly else self._writable_fields
 
         if field_names is not None:
             fields = [f for f in fields if f[0] in field_names]

src/infi/clickhouse_orm/utils.py

@@ -17,15 +17,18 @@ SPECIAL_CHARS = {
 SPECIAL_CHARS_REGEX = re.compile("[" + ''.join(SPECIAL_CHARS.values()) + "]")
 
 
+
 def escape(value, quote=True):
     '''
     If the value is a string, escapes any special characters and optionally
     surrounds it with single quotes. If the value is not a string (e.g. a number), 
     converts it to one.
     '''
+    def escape_one(match):
+        return SPECIAL_CHARS[match.group(0)]
+
     if isinstance(value, string_types):
-        if SPECIAL_CHARS_REGEX.search(value):
-            value = "".join(SPECIAL_CHARS.get(c, c) for c in value)
+        value = SPECIAL_CHARS_REGEX.sub(escape_one, value)
         if quote:
             value = "'" + value + "'"
     return text_type(value)