He can do everything except the ones listed above. Q What is the difference between a primary key and a unique key? A A column defined as a primary key does not allow null values. Q What are dirty reads? Q How do I insert duplicate rows in a unique index?
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He can do everything except the ones listed above. Q What is the difference between a primary key and a unique key? A A column defined as a primary key does not allow null values. Q What are dirty reads? Q How do I insert duplicate rows in a unique index? Q Which index you prefer for a table that has lot of updations and insertions? A A non-clustered index. Because the clustered index rewrites the whole data in the table based on updations and insertions. Q What are segments?
What are the uses of segments? A segment is a named sub-set of a database device. It is basically used in fine tuning or optimizing the performance of the server. Placing a table on one segment and its non-clustered index on another segment causes the reads and writes to be faster. Q What are procedures and what are the uses of procedures?
A They are system procedures and stored procedures. Uses of procedures are Take parameters Return a status value to a calling procedure or batch to indicate success or failure, and the reason for failure. Return values of parameters to a calling procedure or batch be executed on remote sql Servers Q What is the difference between executing a set of statements in a batch and executing the statements in a procedure?
A batch takes more time than procedure, because it writes in syslogs. Q What will you do if one out of five users complaints that his system is working slow? X calls another procedure Y. A Yes. Q What is the difference between truncate and delete?
Q What are the restrictions on updating a table through views? Q What is Intent lock? A intent locks indicate the intention to acquire a shared or exclusive lock on a data page. Intent locks are used to prevent other transactions from acquiring shared or exclusive locks on the given page it is a table lock.
Q How do I call a remote procedure? Therefore complete recovery becomes impossible if the database fails or gets corrupted. To have a copy of all changes made, we should dump database. Q What databases are created during installation? A Four databases are created during installation. They are a master b model c tempdb d sybsystemprocs. Q How to display the current users role? When a record is deleted, what happens to the remaining records on that page? No physical movement of data occurs at the time of record is deleted.
The record is tagged for future physical deletion. When does sybase reduce the amount of space allocated to an object when a large number of records have been deleted? When no more records reside on an extent, the extent is returned to the pool for use by other objects. There are several ways to accomplish this. One way is to drop the clustered index and re-create it. Another way is to bcp out, truncate table deallocate extents and then bcp in the data allocating only enough extents to hold the data Explain what happens when clustered index is created?
What happens when non-clustered index was created? A leaf level is created by copying the specified index columns. The leaf level is sorted and uses pointers to the associated data pages. The Backup Server Why would we define a fill factor when creating an index? How do we increase the size of database? Alter database What utility does sybase use to import large volumes of data? BCP When fast bcp is used to load data, what effect does it have on the transaction log? When fast BCP is used syb does not log any transactions.
What is stored in syslogs? Would frequent transaction log dumps be used for an application classified as decision support or on line transaction processing? On line transaction processing What happens when we try to create unique index on a column that contains duplicate values?
Does Syb allows null values in a column with unique index? We can complete update the process purpose. It updates the all transactions, page allocations.
Describe some scenarios that would cause the transaction log to fill up. What are the DBCC commands? If the database corrupted, then we can repair through dbcc dbrepair. If the transactions log is full. If an old transaction remains open and is causing the log to fill up, what should you do?
How to change configure the values? If syslogs of a database was full what are the steps taken? The leaf level of the clustered index is the data.
What does update statement do? What are the constraints in sybase? What does dump database does and dump tran does? Will a file containing rows that have negative values for column b be added during a bulk-copy? What command you use to change the default value in column b to 5? How many pages are allocated when a table is created? What is difference between varchar and char? How many no of triggers can be created on a table?
You usually wind up with more tables. You can have more clustered indexes you get only one per table so you get more flexibility in tuning queries. Index searching is often faster, since indexes tend to be narrower and shorter.
More tables allow better use of segments to control physical placement of data. You usually wind up with fewer indexes per table, so data modification commands are faster. You wind up with fewer null values and less redundant data, making your database more compact.
Triggers execute more quickly if you are not maintaining redundant data. Data modification anomalies are reduced.
Normalization is conceptually cleaner and easier to maintain and change as you needs change. While fully normalized databases require more joins, joins are generally very fast if indexes are available on the join columns. The cost of finding rows already in the data cache is extremely low.
What types of relationships in sybase10? What is data integrity types? How to update row by row from the database? What are the system tables in sybase10? What is difference between sybase 4. How many types of locks? How to create data type? What type of locking will sybase follow: Row level, Column Level? What is the diff between Implicit and Non-Implicit cursors?. What are sub-related queries, Diff type of Triggers Automated Triggers?.
What are diff type of backups in Unix environment?.
SQL Server DBA Interview Questions and Answers
I suppose that it is theoretically possible that both would fallback for some reason, but it seems unlikely. Amazing, it all worked! The main problem that you will encounter is not lack of communication but lack of features. The facility to bcp out of views was added to the Which is not bad when you remember that Powerbuilder 3 only talked 4.
Sybase Interview Questions
There are also some questions the candidate might want to ask before s he takes the job see the end of this page. Please bear in mind that these are just some suggestions which I personally think are relevant. You could use these as a starting point and add further questions of your own. The questions are listed here. They are repeated, with answers, below.