Asked by: Sonnia Cachaza
technology and computing databases

What is uncommitted read in db2?

Last Updated: 12th August, 2021

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Since V4, DB2 has provided read-through locks, also know as “dirty read” or “uncommitted read,” to help overcome concurrency problems. When using an uncommitted reads an application program can read data that has been changed, but is not yet committed.

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Correspondingly, what does uncommitted read mean?

READ UNCOMMITTED. Specifies that statements can read rows that have been modified by other transactions but not yet committed. Transactions running at the READ UNCOMMITTED level do not issue shared locks to prevent other transactions from modifying data read by the current transaction.

Subsequently, question is, what is the default isolation level in db2? CS is perhaps the most common DB2 isolation level in use in production applications because it offers a good tradeoff between data integrity and concurrency. When CS is specified the transaction will never read data that is not yet committed; only committed data can be read.

Also to know, what is the meaning of With Ur in db2?

Uncommitted Read (UR) -- also known as "dirty read" or "read through locks" -- is one of the most useful features of DB2 V4. 1. Two ways to invoke UR: Bind the plan or package with ISOLATION(UR). This will override the isolation level with which the plan or package was bound.

What is isolation level in db2 and its types?

Database can be accessed by the multiple users at a time (Concurrency). The Isolation level is the way to maintain the concurrency for the multiple users by setting the levels of access to the database. ISOLATION is the BIND parameter which will determine the page lock duration. CS ------ Cursor Stability.

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