What is a pseudo key? What is its use???
Answers were Sorted based on User's Feedback
Answer / tdguy
If a table in a database either has no natural key or the
natural key is so long that using it as the key would be
inefficient then we need to consider using a pseudokey
instead. Pseudokeys are usually given the same name as the
table they belong to with _id added to the end of the name.
They usually are defined to contain a number and use
autoincrement in mySQL or the equivalent in other versions
of SQL to dynamically allocate a value when new rows are
created.
source: http://www.felgall.com/mysql04.htm
| Is This Answer Correct ? | 6 Yes | 0 No |
Answer / guest
it is used in locks the rowhash
best to tell EXPLAIN in this explanation we locks pseudo key
then it start
| Is This Answer Correct ? | 0 Yes | 10 No |
What are default access rights in teradata? What explicit right can be given to a user?
What are the differences between TerdataV2R5 and V12 Versions please??
I Have Name field in a Table Name ------------- abcde;fgh;ijk; abc;def;jklm;no I want to write a sql to display name field data with out ';'.so i want to replace ; with '' how will write in Teradata
Explain some differences between mpp and smp?
What do you mean by tpt in teradata?
what is the difference between start schma and Fsldm?
one table have input no name 10 rao 20 siva 30 srinu 10 rao i want to ouput like this way no name 20 siva 30 srinu 10 rao how it posible in only sql server query?not oracle?
How does hashing happens in teradata?
Give a justifiable reason why Multi-load supports NUSI instead of USI.
What is meant by a Virtual Disk?
How to Skip or Get first and Last Record from Flat File through MultiLoad and TPUMP Utility?
What are the different design perspectives used in teradata?