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| author | Erik Johnston <erik@matrix.org> | 2019-05-16 16:41:05 +0100 |
|---|---|---|
| committer | Erik Johnston <erik@matrix.org> | 2019-05-16 16:41:05 +0100 |
| commit | 895179a4dcc993af9702e3ab36e5d2157fdd0c26 (patch) | |
| tree | 3924530367caf45c26ef25e34eedba4f0cb2b989 /synapse/storage/stream.py | |
| parent | Newsfile (diff) | |
| download | synapse-895179a4dcc993af9702e3ab36e5d2157fdd0c26.tar.xz | |
Update docstring
Diffstat (limited to 'synapse/storage/stream.py')
| -rw-r--r-- | synapse/storage/stream.py | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/synapse/storage/stream.py b/synapse/storage/stream.py index 163363c0c2..824e77c89e 100644 --- a/synapse/storage/stream.py +++ b/synapse/storage/stream.py @@ -77,6 +77,15 @@ def generate_pagination_where_clause( would be generated for dir=b, from_token=(6, 7) and to_token=(5, 3). + Note that tokens are considered to be after the row they are in, e.g. if + a row A has a token T, then we consider A to be before T. This covention + is important when figuring out inequalities for the generated SQL, and + produces the following result: + - If paginatiting forwards then we exclude any rows matching the from + token, but include those that match the to token. + - If paginatiting backwards then we include any rows matching the from + token, but include those that match the to token. + Args: direction (str): Whether we're paginating backwards("b") or forwards ("f"). @@ -131,7 +140,9 @@ def _make_generic_sql_bound(bound, column_names, values, engine): names (tuple[str, str]): The column names. Must *not* be user defined as these get inserted directly into the SQL statement without escapes. - values (tuple[int, int]): The values to bound the columns by. + values (tuple[int|None, int]): The values to bound the columns by. If + the first value is None then only creates a bound on the second + column. engine: The database engine to generate the SQL for Returns: |