def __init__(self, **kwargs):
super(RangePartition, self).__init__(**kwargs)
self.partition_range = kwargs['partition_range']
self.partition_subtype = kwargs['partition_subtype']
self.datetime = DateTime(self.column_value)
def __init__(self, **kwargs):
super(RangePartition, self).__init__(**kwargs)
self.partition_range = kwargs['partition_range']
self.partition_subtype = kwargs['partition_subtype']
self.datetime = DateTime(self.column_value)
class RangePartition(Partition):
"""Range partition type implementation"""
def __init__(self, **kwargs):
super(RangePartition, self).__init__(**kwargs)
self.partition_range = kwargs['partition_range']
self.partition_subtype = kwargs['partition_subtype']
self.datetime = DateTime(self.column_value)
def prepare(self):
"""Prepares table for partitioning"""
super(RangePartition, self).prepare()
return self.database.execute("""
-- We need to create zero partition to speed up things due to the partitioning
-- implementation in the early versions of MySQL database (see bug #49754)
ALTER TABLE {parent_table} PARTITION BY RANGE ({function}({partition_column}))(
PARTITION {partition_pattern} VALUES LESS THAN (0)
);
""".format(
parent_table=self.table,
partition_column=self.column_name,
partition_pattern=self._get_name(),
function=self._get_partition_function()
))
def create(self):
"""Creates new partition"""
return self.database.execute("""
ALTER TABLE {parent_table} ADD PARTITION (
PARTITION {child_table} VALUES LESS THAN ({function}('{period_end}') + {addition})
);
""".format(
child_table=self._get_name(),
parent_table=self.table,
function=self._get_partition_function(),
period_end=self.datetime.get_period(self.partition_range)[1],
addition='86400' if self._get_column_type() == 'timestamp' else '1'
))
def _get_name(self):
"""Dynamically defines new partition name depending on the partition subtype"""
try:
return getattr(self, '_get_{0}_name'.format(self.partition_subtype))()
except AttributeError:
import re
raise PartitionRangeSubtypeError(
model=self.model,
dialect=self.dialect,
current=self.partition_subtype,
allowed=[re.match('_get_(\w+)_name', c).group(1) for c in dir(
self) if re.match('_get_\w+_name', c) is not None]
)
def _get_date_name(self):
"""Defines name for a new partition for date partition subtype"""
patterns = {
'day': {'real': 'y%Yd%j', 'none': 'y0000d000'},
'week': {'real': 'y%Yw%V', 'none': 'y0000w00'},
'month': {'real': 'y%Ym%m', 'none': 'y0000m00'},
'year': {'real': 'y%Y', 'none': 'y0000'},
}
try:
if self.column_value is None:
pattern = patterns[self.partition_range]['none']
else:
pattern = self.column_value.strftime(patterns[self.partition_range]['real'])
except KeyError:
raise PartitionRangeError(
model=self.model,
dialect=self.dialect,
current=self.partition_range,
allowed=patterns.keys()
)
return '{0}_{1}'.format(self.table, pattern)
def _get_partition_function(self):
"""Returns correct partition function depending on the MySQL column type"""
functions = {
'date': 'TO_DAYS',
'datetime': 'TO_DAYS',
'timestamp': 'UNIX_TIMESTAMP',
}
column_type = self._get_column_type()
try:
return functions[column_type]
except KeyError:
raise PartitionFunctionError(
model=self.model,
dialect=self.dialect,
current=column_type,
allowed=functions.keys()
)
def _get_column_type(self):
"""Returns real database column type"""
return self.database.select_one("""
SELECT data_type
FROM information_schema.columns
WHERE table_name = '{parent_table}' AND column_name = '{partition_column}';
""".format(
parent_table=self.table,
partition_column=self.column_name
))
class RangePartition(Partition):
"""Range partition type implementation"""
def __init__(self, **kwargs):
super(RangePartition, self).__init__(**kwargs)
self.partition_range = kwargs['partition_range']
self.partition_subtype = kwargs['partition_subtype']
self.datetime = DateTime(self.column_value)
def prepare(self):
"""Prepares table for partitioning"""
super(RangePartition, self).prepare()
return self.database.execute("""
-- We need to create zero partition to speed up things due to the partitioning
-- implementation in the early versions of MySQL database (see bug #49754)
ALTER TABLE {parent_table} PARTITION BY RANGE ({function}({partition_column}))(
PARTITION {partition_pattern} VALUES LESS THAN (0)
);
""".format(parent_table=self.table,
partition_column=self.column_name,
partition_pattern=self._get_name(),
function=self._get_partition_function()))
def create(self):
"""Creates new partition"""
return self.database.execute("""
ALTER TABLE {parent_table} ADD PARTITION (
PARTITION {child_table} VALUES LESS THAN ({function}('{period_end}') + {addition})
);
""".format(child_table=self._get_name(),
parent_table=self.table,
function=self._get_partition_function(),
period_end=self.datetime.get_period(
self.partition_range)[1],
addition='86400'
if self._get_column_type() == 'timestamp' else '1'))
def _get_name(self):
"""Dynamically defines new partition name depending on the partition subtype"""
try:
return getattr(self,
'_get_{0}_name'.format(self.partition_subtype))()
except AttributeError:
import re
raise PartitionRangeSubtypeError(
model=self.model,
dialect=self.dialect,
current=self.partition_subtype,
allowed=[
re.match('_get_(\w+)_name', c).group(1) for c in dir(self)
if re.match('_get_\w+_name', c) is not None
])
def _get_date_name(self):
"""Defines name for a new partition for date partition subtype"""
patterns = {
'day': {
'real': 'y%Yd%j',
'none': 'y0000d000'
},
'week': {
'real': 'y%Yw%V',
'none': 'y0000w00'
},
'month': {
'real': 'y%Ym%m',
'none': 'y0000m00'
},
'year': {
'real': 'y%Y',
'none': 'y0000'
},
}
try:
if self.column_value is None:
pattern = patterns[self.partition_range]['none']
else:
pattern = self.column_value.strftime(
patterns[self.partition_range]['real'])
except KeyError:
raise PartitionRangeError(model=self.model,
dialect=self.dialect,
current=self.partition_range,
allowed=patterns.keys())
return '{0}_{1}'.format(self.table, pattern)
def _get_partition_function(self):
"""Returns correct partition function depending on the MySQL column type"""
functions = {
'date': 'TO_DAYS',
'datetime': 'TO_DAYS',
'timestamp': 'UNIX_TIMESTAMP',
}
column_type = self._get_column_type()
try:
return functions[column_type]
except KeyError:
raise PartitionFunctionError(model=self.model,
dialect=self.dialect,
current=column_type,
allowed=functions.keys())
def _get_column_type(self):
"""Returns real database column type"""
return self.database.select_one("""
SELECT data_type
FROM information_schema.columns
WHERE table_name = '{parent_table}' AND column_name = '{partition_column}';
""".format(parent_table=self.table, partition_column=self.column_name))
