TL/DR:
- only 1 out of 14 statements in a batch do not mutate the partition..
- no error is logged in the application layer, or Cassandra system.log or
Cassandra debug.log
- using C#, and Datastax latest driver
- cluster is a 1-node, dev setup.
- datastax driver configured with LOCAL_QUORUM at the session, and
statement level.
- using preparedstatements.. 1,000% sure there's no typo.. (but I've been
wrong before)
I have about 14 statements that get batched up together. They're updating
at most 2, maybe 3 denormalized tables.. all the same user object, just
different lookup keys.
To help visualize, the tables look a little like these.. abbreviated..
User table..
CREATE TABLE user (u_id uuid, act_id uuid, ext_id text, dt_created
timeuuid, dt_mod timeuuid, is_group Boolean, first_name text)
Users By Account (or plan)
CREATE TABLE user_by_act (act_id uuid, u_id uuid, first_name text)
User By external identifier
CREATE TABLE user_by_ext (ext_id text, u_id uuid, act_id uuid, first_name
text)
I create a batch that updates all the tables.. various updates are broken
out into separate statements, so for example, there's a statement that
updates the external ID in the 'user' table.
UPDATE user_by_ext SET ext_id = :ext_id WHERE u_id = :u_id
This particular batch has 14 statements total, across all 3 tables. They
are only updating at most 3 partitions.. a single partition may have 4 or
more statements to update various parts of the partition. e.g. first name
and last name are a single statement added to the batch.
Here's the problem... of those 14 statements.. across the 3 partitions...
ONE and ONLY ONE update doesn't work.. Absolutely every other discreet
update in the whole batch works.
List<BoundStatement> boundStatements = new
List<BoundStatement>();
// *************************
// user table
boundStatements.Add(SessionManager.UserInsertStatement.Bind(new
{ u_id= user.UserId, act_id = user.ActId, dt_created = nowId, dt_mod =
nowId, is_everyone = user.IsEveryone, is_group = user.IsGroup }));
if (!string.IsNullOrWhiteSpace(user.ExtId))
//********************
// this statement gets added to the list.. it is part of the batch
// but it NEVER updates the actual field in the databse.
// I have moved it around.. up, down... the only thing that works
// is if I call execute on the first binding above, and then add the rest
// of these as a separate batch.
boundStatements.Add(SessionManager.UserUpdateExtIdStatement.Bind(new { u_id
= user.UserId, ext_id = user.ExtId, dt_mod = nowId }));
//********************
if (!string.IsNullOrWhiteSpace(user.Email))
boundStatements.Add(SessionManager.UserUpdateEmailStatement.Bind(new { u_id
= user.UserId, email = user.Email, dt_mod = nowId }));
BoundStatement userProfile =
CreateUserProfileBoundStatement(nowId, user);
if (userProfile != null)
boundStatements.Add(userProfile);
// *************************
// user_by_act table
CreateUserAccountInsertBoundStatements(boundStatements, user,
nowId);
// *************************
// user_by_ext table
if (!string.IsNullOrWhiteSpace(user.ExtId))
{
boundStatements.Add(SessionManager.UserExtInsertStatement.Bind(new { ext_id
= user.ExtId, act_id = user.ActId, dt_created = nowId, dt_mod = nowId,
is_group = user.IsGroup, u_id = user.UserId }));
BoundStatement userByExtProfile =
CreateUserByExtProfileBoundStatement(nowId, user);
if (userByExtProfile != null)
boundStatements.Add(userByExtProfile);
if (!string.IsNullOrWhiteSpace(user.Email))
boundStatements.Add(SessionManager.UserExtUpdateEmailStatement.Bind(new {
ext_id = user.ExtId, email = user.Email, dt_mod = nowId }));
}
--
Randy Lynn
rl...@getavail.com
office:
859.963.1616 <+1-859-963-1616> ext 202
163 East Main Street - Lexington, KY 40507 - USA
<https://www.getavail.com/> getavail.com <https://www.getavail.com/>
