What is a transaction and what are ACID properties?
Answer Posted / hloni
A transaction is a sequence of database operations that
access the database. It must be a logical unit of work,
meaning that no portion of the transaction can exist on its
own. Either all parts are executed or the transaction is
aborted.
Transaction has five main properties called ACIDS:
1. Atomicity -- all parts of the transaction are executed
or else the transaction is aborted.
2. Consistency -- indicates the permanence of the
database's consistent state. When a transaction is
completed the database reaches a consistence state.
3. Isolation -- means that the data used during the
exercution of a transaction cannot be used by the a second
transaction until the first transaction is complete.
4. Durability -- ensures that once transaction changes are
commited, they cannot be lost even in the event of system
failure.
5. Serializability -- ensures that concurrent execution of
several transaction yields consistent results. This
property is important in a multi-user and distributed
datbases, where multiple transaction are likely to be
executed concurrently.
| Is This Answer Correct ? | 14 Yes | 10 No |
Post New Answer View All Answers
Explain iaas, paas and saas?
hi, the following are the outputs of sp_spaceused and sp_tempdbspace sp_spaceused ------------ database size unallocated size tempdb 77752.95 MB 28026.99 MB sp_tempdbspace ------------- database size spaceused tempdb 77752.945312 1.007812 the unused space in sp_spaceused is nearly 28 Gb and in sp_tempdbspace is nearly 76 Gb cany any one explain about this output and why its giving different results.
What is self contained multi valued query?
How to get the definition of a trigger back?
What is a constant or literal in ms sql server?
What is a primary index?
explain what are the steps you will take, if you are tasked with securing an sql server? : Sql server database administration
What are the 2 types of classifications of constraints in the sql server?
Can we call future method from queueable?
How to manipulate data from one table to another table ?
What is sql language?
What authentication modes does sql server support?
Do you know what are the steps to process a single select statement?
What is sql collation?
What is mssql?