I have some confusion about lock (ROWLOCK ,UPDLock AND xlock). i want to know the difference among these locks. where to use UPDLock, when to use RowLock and when Xlock with a example for better clarification.
BEGINTRANSACTIONSELECT @ID=RowID FROM MyTable WITH (ROWLOCK, XLOCK, HOLDLOCK) WHERE ID=6822
In the above sql rowlock and XLOCK both use as a result from other session records 6822 could not be read or modify. XLOCK alone is capable to lock the rows....so why one should use ROWLOCK & XLOCK together ?
if i use only xlock & HOLDLOCK then it will not serve the purpose ?
2) Tell me with example what is the difference between ROWLOCK & UPDLOCK ?
ROWLOCK prevent other session to modify data and UPDLOCK does the same thing. so what is the difference
between ROWLOCK & UPDLOCK ?
Please anyone explain these difference with example as a result at my end i can run the example code and understand.
I was looking for an efficient way to store "States" of entities in the DB. For example I had OrderStatus and that can be mapped to a table called Status and have the ID and the status Name be present in a join. If however I wanted to add more statuses for other Entity tables I don't want to have to create a new table for every Entity, is there a way to store all these statuses in one table? Thanks
I , the last project I was asked to advise on was managed by a PM who was adamant that this was the "modern" way to go (I was accused of being an old fart who was stuck in the 90's). Started off as a 2 column table and the last I saw of it was a 5 column, 2 table structure.
Luckily I walked away from anything to do with the project.
Never underestimate the power of human stupidity -
I'm old. I know stuff - JSOP
I need help resetting the values of each users in a row at once with random numbers by either button click or loading a page.
Just like a reset page or button to assign random numbers to each users without repeating at once.
I need a real-time database for inserting at least 500fields per second. (I have been selected TimeScaleDB (Postgresql Extension) for my purpose, currently). So, the matrix of the table will be 500(Fields)x86400(Rows).
This means that for a 500 double-precision field it will be around 500*8bytes=4000bytes which for86400rows it will be 345,600,000bytes (345.6M).
I know a software which it is recording the same structure of data and the final daily volume of its database is only 84M~85M. Its Extension is*.tag so, i think it is a DataFlex database. It is not a free database and i also never used it.
1- Which free database is the best to use for real-time data storing and querying (at the moment of storing) based on your experience or knowledge?
2- Is there any database to have such a volume or even less forthis size of data?
Thank you for your Help.