A mechanism for committing a consistent set of changes into a database atomically.

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Concurrent Transactions vs Simultaneous Transactions

Chapter 6 of David Kroenke's Database Concepts: Database Administration Is my understanding correct that in a database, simultaneous transactions don't really happen. Instead, it is a concurrent ...
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How to UPDATE just one record in DB2?

In DB2, I need to do a SELECT FROM UPDATE, to put an update + select in a single transaction. But I need to make sure to update only one record per transaction. Familiar with the LIMIT clause from ...
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Why is this rollback needed when using sp_addextendedproperty in a stored procedure?

In enter link description here I showed, how I document databases. To insert the extended properties, initially I uses plan sequences of sp_addextendedproperty calls. But lately I wanted to catch ...
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1answer
133 views

Why do row-versioning isolations use a linked list of versions of record? [closed]

Trying to better understand row-versioning based transaction isolations in SQL Server... According to Kimberly L. Tripp, Neal Graves's "SQL Server 2005 Row Versioning-Based Transaction Isolation": ...
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1answer
341 views

Delete all rows within transaction: what would happen to other transactions?

I currently have a function in PostgreSQL that creates a temp table, fills it, performs some tricky selects and returns results. postgresql's temp tables are local to functions, so this helps me avoid ...
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1answer
34 views

Mysql transaction READ REPEATABLE and READ COMMITTED read view [closed]

I've come across something strage using Amazon RDS (MySQL 5.6.23). I had issues when concurrent transactions were locking and then calculating a value from multiple tables. The following is a quick ...
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When does SQL Server acquire locks?

The list of isolation levels in SQL Server found here states that write locks acquired within a transaction are retained until the end of the transaction. However it doesn't mention anything about ...
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2answers
4k views

Will a delete then insert within a transaction cascade?

I had a question about what the expected and actual behaviour for the following scenario is. The scenario is one where a database table ([table1]) is cleared and reloaded every day. The table has an ...
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3answers
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Why am i getting deadlocks with 1 read and 1 write thread in SQL

if anyone could please help me understand why the following transactions deadlock? I am providing the 2 transactions and the indexes for each table: Transaction 1: SELECT blockId, blockData, ...
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759 views

Transactions within a Transaction

What behaviour would PostgreSQL display if for example the script below were called BEGIN; SELECT * FROM foo; INSERT INTO foo(name) VALUES ('bar'); BEGIN; <- The point of interest END; Would ...
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545 views

Synonyms and transactions

I'm working with an application that uses SQL synonyms to switch between tables on local and remote databases without duplicating code. BEGIN TRANSACTION if (@isRemote = 1) BEGIN CREATE ...
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1answer
269 views

Does blocking always mean open transaction?

This may seem a bit dull question but does blocking always mean that there is open transaction and that may cause transaction log grow to infinity because open transaction prevents log truncation ...
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mysql transaction vs lock

I have a question regarding MySQL locking and transaction management. My Question is ..does mysql takes lock on the the tuple/table on which I am doing select/update in a transaction ?
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900 views

Find out if two rows came from same transaction in Oracle

I am using Oracle 11.1 and would like to figure out if two rows in one table where inserted by the same transaction. Is there an easy sql statement to map a row to an transactions id? The table is an ...
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1answer
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Why can't I change the isolation levels of my connection in MySQL?

I am trying to experiment a bit with the isolation level of MySQL in a test environment. I do the following: mysql> set @@session.tx_isolation='READ-UNCOMMITED'; ERROR 1231 (42000): Variable ...
3
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1answer
254 views

Is SQL Server Replication transactionally 'safe' across all published tables?

We have a system that has one of its datasources still on SQL Server 2000. In order to achieve higher availability, we are looking to setup transactional replication from this 2000 server to a 2008 ...
3
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1answer
67 views

xp_cmdshell in a transaction

I need to run multiple scripts in a certain folder in a transaction and rollback if there are any errors. At this point I'm just trying to get the rollback to work without a try catch. Currently when ...
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2answers
323 views

How to minimize log operations in SQL Server to avoid “log full” error

I have a database in production which constantly get log file filled, its a data warehouse and have many jobs/queries running for obvious. Below is the error which I am getting Msg 9002, Level 17, ...
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1answer
307 views

Transaction with multiple SQLCMD calls in a batch file

Is there a good way to do something like the following? SQLCMD -S %SERVER% -E -Q "BEGIN TRANSACTION" FOR %%f in (script1 script2 script3) do ( SET CURRENT_SCRIPT=%%f SQLCMD -S Localhost -E -b ...
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1answer
115 views

Effects of turning the transaction safety OFF

I am considering to turn off the transaction safety to maximize the performance. Before that i am interested in finding the current status of transaction safety. Is there any command that we can get ...
3
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1answer
826 views

Complex constraint across all data in a table

We have a table to record processing that occurs on a system and we need to ensure that only a single row has an 'in process' status. I want to ensure that the result of this is always either zero or ...
3
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1answer
339 views

SQL Server 2008 - Adding a column and a filtered index within a single transaction?

This is more of a general question. Why can you not add a filtered index within the same transaction scope as adding the new column in the first place? The solution is of course simple, just make two ...
3
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1answer
2k views

Rotate a table in PostgreSQL

Problem description I need to rotate (with DROP and CREATE) a table which is heavily used by other clients. At present, I have a program which replaces (DROP + CREATE) this table. Sometimes, just ...
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2answers
343 views

What is the correct term to describe a “persistent transaction”?

I'm kind of a the administrator of a zero-administration OODBMS, but mostly I do programming. I remember reading years ago about some SQL database that had a concept of something like a permanent ...
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142 views

Is there a way to “SELECT and TRUNCATE” without losing new data?

I have an application that writes raw log files to a table called new in a PostgreSQL database -- lots of rows and lots of duplicate data. Via a cron job running every minute, I normalize the raw data ...
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2answers
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How do I implement insert-if-not-found for transactions at serializable isolation level?

I'm having a hard time figuring out how to exactly implement a 'insert if not found' function. Consider the following. We have a table called artist with 2 columns, (name, id) where name is the ...
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1answer
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MySQL Insert into two tables using new IDs

I'm trying to select data already in the database and insert it into two tables using the generated ID from table one. table1 contains configuration options, table2 contains pricing data. Table2 uses ...
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1answer
477 views

SQL Server : KEY lock prevents FK on nearby row, but not SELECT [closed]

I have the following table structure (simplified, pseudocode): TABLE dbo.Users (Id int NOT NULL IDENTITY PRIMARY KEY) TABLE dbo.Transfers ( Id int NOT NULL IDENTITY PRIMARY KEY, ...
3
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1answer
149 views

How to perform server-side transaction timeout if COMMIT TRANSACTION will never arrive?

How can SQL Server terminate one of its transactions if it exceeds preset timeout? Imagine the following transaction performed by traveling salesman's SQL client application, which is submitted ...
3
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1answer
637 views

Using the auto increment id from one query as the fk of the next insert

I'm not sure if I'm overcomplicating this or whether I can't see the wood for the trees. I have two tables, both have auto incrementing ID's. Table 1: ID - auto field - int other field - varchar ...
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2answers
685 views

read before write transaction

Talking about transactions (db transactions), does a read operation have always precede a write operation? That's obvious, isn't it? Thanks in advance *Of course my question doesn't take into ...
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1answer
885 views

Duplicate UNIQUE KEY error after ROLLBACK in MySQL

I have a table like this mysql> describe seudonimos; +--------------+------------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra ...
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1answer
131 views

Use of Trigger After a Transaction

I have a scenario where there is a transaction being executed to update a few tables. On one of these tables there is a trigger that accesses the data on those tables, but is only planned to be on ...
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1answer
134 views

Rollback on \include error in psql

I'm trying to execute an sql script file in a single transation. The file contains includes for some other scripts which in my example create some tables. It looks like this: \include ...
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Does MySQL support querying for the current running transaction id

PostgreSQL supports retrieving the current running transaction id using a query like this: select txid_current(); Does MySQL have any such equivalent?
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1answer
721 views

Distributed - across multiple databases or servers - Transactions

I have some doubts related to transactions in SQL. I perform below steps. Connection 1 open for DB1 database Begin transaction for Connection 1 Run the commands on Connection 1 Connection 2 open for ...
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2answers
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Partial rollback doesn't decrement trancount

Suppose I have an open SQL Server session, and do the following: begin tran insert into People (Id) values (1) select @@TRANCOUNT -- Prints 1 save transaction tt begin tran select @@TRANCOUNT ...
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2answers
333 views

Transaction Log Backups

I am working on backup+recovery scenario and I came across a situation where I could not figure out how I would have to deal with it. We have couple databases where sometimes there may not be any ...
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2answers
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Error on DDL statement never invokes CATCH

When I try to close the SS Management Studio window below is the error I understand that DDL statements are implicit COMMIT and the below WARNING message is because BEGIN TRAN never COMMIT or ...
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1answer
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SQL Server - how transactions and transaction log work (simplified)

I have a theory on how transactions work, but I would like if someone could verify it or correct some points if possible. Let's consider we have a database with full recovery model. Now, everything ...
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2answers
252 views

Half of a transaction completes, when the other half fails?

I have done some searching on SO, MSDN, and various other sources, and I found plenty of questions about transactions, but none that seem to be exactly what I'm dealing with. Admittedly I'm still ...
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3answers
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Transaction Isolation level different threads massive number of Writes

I have a lot of threads that writing to DB some data in two tables. tbl_raw_data and tbl_parsed_data where tbl_parsed_data have foreign key to tbl_raw_data. I also need the writing to be superfast. ...
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2answers
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Read Committed Isolation Level

Quote from docs: Read Committed is the default isolation level in PostgreSQL. When a transaction uses this isolation level, a SELECT query (without a FOR UPDATE/SHARE clause) sees only data ...
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1answer
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Rollback generate scripts

During the development of applications users often want to add new modules, business rules etc. So I've often used SQL Server 2008 option to create scripts from the development DB to generate new ...
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2answers
112 views

Modeling invoices and orders

I have a problem in modeling a database that contains orders and invoices. Actually it's more of a problem from a business point of view, but it's related to modeling the database nonetheless. Model ...
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2answers
67 views

Locking issues under transaction on Postgres

I recently got a "Out of shared memory - You might need to increase max_locks_per_transaction" error. This is a long running process where I import a bunch of CSV files after proper processing. I ...
2
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2answers
1k views

Query data before a commit transaction

My understanding is that, in a MS SQL Server Management Studio window, after doing a "begin transaction" and then making some changes like add data to a table , you can only query that table and those ...
2
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1answer
136 views

SSIS Transaction Level for Single Task

I have 3 tasks in a SSIS package. If the final task fails I only want that task to rollback. Do I just set that task to REQUIRED? Or leave it as SUPPORTED? Thanks!
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2answers
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Keep local variable after rollback in mysql

I wish to keep local variable from stored procedure even if rollback occurres. In following procedure, i "register" numbers to users. The procedure takes user_id, value_from and value_to as ...
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2answers
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Separate table for 'scheduled payments' and 'completed payments'?

In a previous financial payments related database I'd worked on, it just had one large transactions table. We would insert scheduled transactions for the future, and when that time came, we'd execute ...