diff options
| author | Tomas Vondra | 2021-06-08 18:22:18 +0000 |
|---|---|---|
| committer | Tomas Vondra | 2021-06-08 18:28:31 +0000 |
| commit | cb92703384e2bb3fa0a690e5dbb95ad333c2b44c (patch) | |
| tree | 644c14c6f86391b0ae60736b36330b0caa387864 /src/interfaces/libpq/libpq-fe.h | |
| parent | d1f0aa7696917213485c03b076b573497a535076 (diff) | |
Adjust batch size in postgres_fdw to not use too many parameters
The FE/BE protocol identifies parameters with an Int16 index, which
limits the maximum number of parameters per query to 65535. With
batching added to postges_fdw this limit is much easier to hit, as
the whole batch is essentially a single query, making this error much
easier to hit.
The failures are a bit unpredictable, because it also depends on the
number of columns in the query. So instead of just failing, this patch
tweaks the batch_size to not exceed the maximum number of parameters.
Reported-by: Hou Zhijie <[email protected]>
Reviewed-by: Bharath Rupireddy <[email protected]>
Discussion: https://postgr.es/m/OS0PR01MB571603973C0AC2874AD6BF2594299%40OS0PR01MB5716.jpnprd01.prod.outlook.com
Diffstat (limited to 'src/interfaces/libpq/libpq-fe.h')
| -rw-r--r-- | src/interfaces/libpq/libpq-fe.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h index 845b4c04c9c..ca733a20048 100644 --- a/src/interfaces/libpq/libpq-fe.h +++ b/src/interfaces/libpq/libpq-fe.h @@ -429,6 +429,8 @@ extern PGresult *PQexecPrepared(PGconn *conn, int resultFormat); /* Interface for multiple-result or asynchronous queries */ +#define PQ_QUERY_PARAM_MAX_LIMIT 65535 + extern int PQsendQuery(PGconn *conn, const char *query); extern int PQsendQueryParams(PGconn *conn, const char *command, |