Tag: transactions

EF Core transaction lifetime

c# entity-framework-core sql transactions using

We are using our select statement inside transaction scope because of concurrency concerns. The question is, if I put my transaction in using statement, do I still have to call Commit() method explicitly to be sure that the transaction is closed or Dispose() method will do the job? Here’s example code: Answer The official docs would be your best friend

Returning a value before committing transaction and (UPDLOCK, HOLDLOCK)

c# sql sql-server transactions

I need to check if a record exists – if yes: then returns its id, if not: creates a new record and returns its id. I am using WITH (UPDLOCK, HOLDLOCK) in SELECT to prevent from duplicates (it creates lock). I wonder if I should commit the transaction if a record exists in a database for realising the lock? Answer

Is start transaction always needed with Mariadb storedprocedure?

mariadb sql stored-procedures transactions

I have a mariadb database and a stored procedure. If a select statement is true then a delete query is done. Like this: My question is, do I need to place the start transaction at the beginning before the select statement or is the following possible? This second code doesn’t require a rollback and only does a start transaction when

Why does MySQL not lock rows while searching indexed column

innodb mysql sql transactions

For example, I lock some rows: c2 is not indexed. It means MySQL has to search entire table and if it read uncommitted or read committed isolation levels it places locks on every scanned row and if it doesn’t satisfy the WHERE condition it immediately release the lock. If it is repeatable read those locks that do not satisfy the

PostgreSQL: deadlock without a transaction

deadlock node.js postgresql sql transactions

I have a route (in a node JS app) that inserts and updates some data in a PostgreSQL database (version 13). In pseudo-code, here are all queries that are done in sequential order: On some instances of the app without that much traffic that writes on their own table, I have many deadlocks. I don’t understand why since there is

SQL – on which context do SELECT…FOR UPDATE and UPDATE work?

sql transactions

I would like to have a question about data contexts on which do the transaction operate with different commands. Are there any differences in SELECT…FOR UPDATE and UPDATE in terms of contexts of data? What I mean by this: if I run the following transaction (pseudo-code): What this actually does is that it locks the user in exclusive mode and

Tag: transactions

EF Core transaction lifetime

Returning a value before committing transaction and (UPDLOCK, HOLDLOCK)

Is start transaction always needed with Mariadb storedprocedure?

Why does MySQL not lock rows while searching indexed column

PostgreSQL: deadlock without a transaction

SQL – on which context do SELECT…FOR UPDATE and UPDATE work?

How exactly transactions work in Microsoft SQL Server

Is it possible to lock on a value of a column in SQL Server?

Create database transaction and commit/rollback later [closed]

Why is my “CREATE INDEX CONCURRENTLY ..” command blocked by a “SELECT FROM” query? (Postgres 9.6)