ConditionalRow(row_key, table, filter_)
Google Cloud Bigtable Row for sending mutations conditionally.
Each mutation has an associated state: :data:True
or :data:False
.
When commit
-ed, the mutations for the :data:True
state will be applied if the filter matches any cells in
the row, otherwise the :data:False
state will be applied.
A ConditionalRow
accumulates mutations in the same way a
DirectRow
does:
set_cell
delete
delete_cell
delete_cells
with the only change the extra state
parameter::
row_cond = table.row(b'row-key2', filter_=row_filter) row_cond.set_cell(u'fam', b'col', b'cell-val', state=True) row_cond.delete_cell(u'fam', b'col', state=False)
Parameters |
|
---|---|
Name | Description |
row_key |
bytes
The key for the current row. |
table |
Table
The table that owns the row. |
filter_ |
Filter to be used for conditional mutations. |
Properties
row_key
Row key.
For example:
.. literalinclude:: snippets_table.py :start-after: [START bigtable_api_row_row_key] :end-before: [END bigtable_api_row_row_key] :dedent: 4
Returns | |
---|---|
Type | Description |
bytes |
The key for the current row. |
table
Row table.
For example:
.. literalinclude:: snippets_table.py :start-after: [START bigtable_api_row_table] :end-before: [END bigtable_api_row_table] :dedent: 4
Returns | |
---|---|
Type | Description |
table: Table |
table: The table that owns the row. |
Methods
clear
clear()
Removes all currently accumulated mutations on the current row.
For example:
.. literalinclude:: snippets_table.py :start-after: [START bigtable_api_row_clear] :end-before: [END bigtable_api_row_clear] :dedent: 4
commit
commit()
Makes a CheckAndMutateRow
API request.
If no mutations have been created in the row, no request is made.
The mutations will be applied conditionally, based on whether the
filter matches any cells in the ConditionalRow
or not. (Each
method which adds a mutation has a state
parameter for this
purpose.)
Mutations are applied atomically and in order, meaning that earlier mutations can be masked / negated by later ones. Cells already present in the row are left unchanged unless explicitly changed by a mutation.
After committing the accumulated mutations, resets the local mutations.
For example:
.. literalinclude:: snippets_table.py :start-after: [START bigtable_api_row_commit] :end-before: [END bigtable_api_row_commit] :dedent: 4
Exceptions | |
---|---|
Type | Description |
`ValueErro |
Returns | |
---|---|
Type | Description |
bool |
Flag indicating if the filter was matched (which also indicates which set of mutations were applied by the server). |
delete
delete(state=True)
Deletes this row from the table.
.. literalinclude:: snippets_table.py :start-after: [START bigtable_api_row_delete] :end-before: [END bigtable_api_row_delete] :dedent: 4Parameter | |
---|---|
Name | Description |
state |
bool
(Optional) The state that the mutation should be applied in. Defaults to :data: |
delete_cell
delete_cell(column_family_id, column, time_range=None, state=True)
Deletes cell in this row.
.. literalinclude:: snippets_table.py :start-after: [START bigtable_api_row_delete_cell] :end-before: [END bigtable_api_row_delete_cell] :dedent: 4Parameters | |
---|---|
Name | Description |
column_family_id |
str
The column family that contains the column or columns with cells being deleted. Must be of the form |
column |
bytes
The column within the column family that will have a cell deleted. |
time_range |
(Optional) The range of time within which cells should be deleted. |
state |
bool
(Optional) The state that the mutation should be applied in. Defaults to :data: |
delete_cells
delete_cells(column_family_id, columns, time_range=None, state=True)
Deletes cells in this row.
.. literalinclude:: snippets_table.py :start-after: [START bigtable_api_row_delete_cells] :end-before: [END bigtable_api_row_delete_cells] :dedent: 4Parameters | |
---|---|
Name | Description |
column_family_id |
str
The column family that contains the column or columns with cells being deleted. Must be of the form |
columns |
The columns within the column family that will have cells deleted. If |
time_range |
(Optional) The range of time within which cells should be deleted. |
state |
bool
(Optional) The state that the mutation should be applied in. Defaults to :data: |
set_cell
set_cell(column_family_id, column, value, timestamp=None, state=True)
Sets a value in this row.
The cell is determined by the row_key
of this
ConditionalRow
and the column
. The column
must be in
an existing .ColumnFamily
(as determined by
column_family_id
).
Parameters | |
---|---|
Name | Description |
column_family_id |
str
The column family that contains the column. Must be of the form |
column |
bytes
The column within the column family where the cell is located. |
value |
bytes or
The value to set in the cell. If an integer is used, will be interpreted as a 64-bit big-endian signed integer (8 bytes). |
timestamp |
(Optional) The timestamp of the operation. |
state |
bool
(Optional) The state that the mutation should be applied in. Defaults to :data: |