Answer: In Log Shipping the transactional log file from one server is automatically updated in backup database on the other server and in the case when one server fails the other server will have the same DB and we can use this as the DDR(disaster recovery) plan.
Question: What are the null values in SQL SERVER ?
Answer: Before understand the null values we have some overview about what the value is. Value is the actual data stored in a particular field of particular record. But what is done when there is no values in the field.That value is something like
Question: What is difference between OSQL and Query Analyzer ?
Answer: Both are same for functioning but there is a little difference OSQL is command line tool which execute query and display the result same a Query Analyzer do but Query Analyzer is graphical.OSQL have not ability like Query Analyzer to analyze queries and show statistics on speed of execution .And other useful thing about OSQL is that its helps in scheduling which is done in Query Analyzer with the help of JOB.
Question: What are the different types of Locks ?
Answer: There are three main types of locks that SQL Server
(1)Shared locks are used for operations that does not allow to change or update data, such as a SELECT statement.
(2)Update locks are used when SQL Server intends to modify a page, and later promotes the update page lock to an exclusive page lock before actually making the changes.
(3)Exclusive locks are used for the data modification operations, such as UPDATE, INSERT, or DELETE.
Question: Explain some SQL Server 2000 Query?
Answer: Here are some sql server 2000 query like Sql Insert Query, Delete Sql Query, Update Sql Query and Sql Create Query:
1) Sql Insert Query:
a) How to encrypt data by using Sql Insert Query.
--: insert into table_name(Tablecolumn1, tablecolumn2,. . . . .) values ('value1', pwdencrypt('value'),. . . .)
b) How to copy data from one table to another with the help of Sql Insert Query.
--: insert into table_name(column1,column2,. . . . ) select column1, column2, . . . . from table_name2
c) Sql Insert Query using where clause
--: insert into tablename(column1,column2) select column1,column2 from tablename2 where id=value.
Question: What is 'Write-ahead log' in Sql Server 2000 ?
Answer: Before understanding it we must have an idea about the transaction log files. These files are the files which holds the data for change in database .
Now we explain when we are doing some Sql Server 2000 query or any Sql query like Sql insert query,delete sql query,update sql query and change the data in sql server database it cannot change the database directly to table .Sql server extracts the data that is modified by sql server 2000 query or by sql query and places it in memory.Once data is stores in memory user can make changes to that a log file is gernated this log file is gernated in every five mintues of transaction is done. After this sql server writes changes to database with the help of transaction log files. This is called Write-ahead log.
Question: What do u mean by Extents and types of Extends ?
Answer: An Extent is a collection of 8 sequential pages to hold database from becoming fregmented. Fragment means these pages relates to same table of database these also holds in indexing. To avoid for fragmentation Sql Server assign space to table in extents. So that the Sql Server keep upto date data in extents. Because these pages are continously one after another. There are usually two types of extends:-Uniform and Mixed.
Uniform means when extent is own by a single object means all collection of 8 ages hold by a single extend is called uniform.
Mixed mean when more then one object is comes in extents is known as mixed extents.
Question: What is different in Rules and Constraints ?
Answer: Rules and Constraints are similar in functionality but there is a An little diffrence between them.Rules are used for backward compatibility . One the most exclusive diffrence is that we an bind rules to a datatypes whereas constraints are bound only to columns.So we can create our own datatype with the help of Rules and get the input according to that.
Question: What is defaults in Sql Server and types of Defaults ?
Answer: Defaults are used when a field of columns is allmost common for all the rows for example in employee table all living in delhi that value of this field is common for all the row in the table if we set this field as default the value that is not fill by us automatically fills the value in the field its also work as intellisense means when user inputing d it will automatically fill the delhi . There are two types of defaults object and definations.
Object deault:-These defaults are applicable on a particular columns . These are usually deined at the time of table designing.When u set the object default field in column state this column in automatically field when u left this filed blank.
Defination default:-When we bind the datatype with default let we named this as dotnet .Then every time we create column and named its datatype as dotnet it will behave the same that we set for dotnet datatype.
Question: What Is Database ?
Answer: A database is similar to a data file in that it is a storage place for data. Like a data file, a database does not present information directly to a user; the user runs an application that accesses data from the database and presents it to the user in an understandable format.Database systems are more powerful than data files in that data is more highly organized. In a well-designed database, there are no duplicate pieces of data that the user or application must update at the same time. Related pieces of data are grouped together in a single structure or record, and relationships can be defined between these structures and records.When working with data files, an application must be coded to work with the specific structure of each data file. In contrast, a database contains a catalog that applications use to determine how data is organized. Generic database applications can use the catalog to present users with data from different databases dynamically, without being tied to a specific data format. A database typically has two main parts: first, the files holding the physical database and second, the database management system (DBMS) software that applications use to access data. The DBMS is responsible for enforcing the database structure, including: · Maintaining relationships between data in the database. Ensuring that data is stored correctly, and that the rules defining data relationships are not violated. · Recovering all data to a point of known consistency in case of system failures.
Question: what is Relational Database ?
Answer: Although there are different ways to organize data in a database, relational databases are one of the most effective. Relational database systems are an application of mathematical set theory to the problem of effectively organizing data. In a relational database, data is collected into tables (called relations in relational theory). A table represents some class of objects that are important to an organization. For example, a company may have a database with a table for employees, another table for customers, and another for stores. Each table is built of columns and rows (called attributes and tuples in relational theory). Each column represents some attribute of the object represented by the table. For example, an Employee table would typically have columns for attributes such as first name, last name, employee ID, department, pay grade, and job title. Each row represents an instance of the object represented by the table. For example, one row in the Employee table represents the employee who has employee ID 12345. When organizing data into tables, you can usually find many different ways to define tables. Relational database theory defines a process called normalization, which ensures that the set of tables you define will organize your data effectively.
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