Concurrent reading in oracle? -
say have customer table has record
custid lastname 1 hamlin
in 1 request customer last name hamlin custid=1. update last name kathy not commit it.
another request comes try last name custid=1. kathy or hamlin.
my understanding if both request different connection object(which should case) second request see hamlin. if same connection object , second request object see last name kathy. p
lease let me know if above understanding correct?
since you're in read-committed transaction isolation level (or higher, oracle supports no lower), not see changes made uncommitted other transactions, ever. beware in serializable mode, query may required wait other transaction commit or rollback, or alternatively transaction may rolled you.
oracle supports read committed , serializable (you can pick, e.g., via set transaction isolation level
); other database systems additional support read-uncommitted, allow see updated not yet committed value.
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