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If @@Rowcount is CHECKED after Error CHECKING statement then it will have 0 as the value of @@Recordcount as it would have been reset. And if @@Recordcount is checked before the error‐checking statement then @@Error would get reset. To get @@error and @@rowcount at the same time do both in same statement and store them in local variable. SELECT @RC = @@ROWCOUNT, @ER = @@ERROR.

If @@Rowcount is checked after Error checking statement then it will have 0 as the value of @@Recordcount as it would have been reset. And if @@Recordcount is checked before the error‐checking statement then @@Error would get reset. To get @@error and @@rowcount at the same time do both in same statement and store them in local variable. SELECT @RC = @@ROWCOUNT, @ER = @@ERROR.

A NOT NULL CONSTRAINT enforces that the COLUMN will not accept null values. The not null constraints are used to enforce domain integrity, as the check constraints.

A NOT NULL constraint enforces that the column will not accept null values. The not null constraints are used to enforce domain integrity, as the check constraints.

A CHECK CONSTRAINT is USED to limit the values that can be PLACED in a column. The check constraints are used to enforce DOMAIN integrity.

A CHECK constraint is used to limit the values that can be placed in a column. The check constraints are used to enforce domain integrity.

A FOREIGN KEY constraint PREVENTS any actions that would destroy links between tables with the corresponding DATA values. A foreign key in one table points to a primary key in ANOTHER table. Foreign keys prevent actions that would LEAVE rows with foreign key values when there are no primary keys with that value. The foreign key CONSTRAINTS are used to enforce referential integrity.

A FOREIGN KEY constraint prevents any actions that would destroy links between tables with the corresponding data values. A foreign key in one table points to a primary key in another table. Foreign keys prevent actions that would leave rows with foreign key values when there are no primary keys with that value. The foreign key constraints are used to enforce referential integrity.

A UNIQUE constraint enforces the uniqueness of the VALUES in a set of columns, so no duplicate values are ENTERED. The unique key CONSTRAINTS are used to enforce entity integrity as the PRIMARY key constraints.

A UNIQUE constraint enforces the uniqueness of the values in a set of columns, so no duplicate values are entered. The unique key constraints are used to enforce entity integrity as the primary key constraints.

A PRIMARY KEY constraint is a unique identifier for a ROW within a database table. Every table should have a primary key constraint to UNIQUELY identify each row and only one primary key constraint can be created for each table. The primary key CONSTRAINTS are used to enforce entity integrity.

A PRIMARY KEY constraint is a unique identifier for a row within a database table. Every table should have a primary key constraint to uniquely identify each row and only one primary key constraint can be created for each table. The primary key constraints are used to enforce entity integrity.

STUFF function is used to overwrite existing CHARACTERS. Using this syntax, STUFF (string_expression, START, length, replacement_characters), string_expression is the string that will have characters substituted, start is the starting position, length is the number of characters in the string that are substituted, and replacement_ characters are the new characters interjected into the string. REPLACE function to replace existing characters of all occurrences. Using the syntax REPLACE (string_expression, search_string, replacement_string), where every incidence of search_string FOUND in the string_expression will be replaced with replacement_string.

STUFF function is used to overwrite existing characters. Using this syntax, STUFF (string_expression, start, length, replacement_characters), string_expression is the string that will have characters substituted, start is the starting position, length is the number of characters in the string that are substituted, and replacement_ characters are the new characters interjected into the string. REPLACE function to replace existing characters of all occurrences. Using the syntax REPLACE (string_expression, search_string, replacement_string), where every incidence of search_string found in the string_expression will be replaced with replacement_string.

A LOCAL temporary table exists only for the duration of a connection or, if defined inside a COMPOUND STATEMENT, for the duration of the compound statement.

A global temporary table remains in the database permanently, but the rows exist only within a GIVEN connection. When connection is closed, the DATA in the global temporary table disappears. However, the table definition remains with the database for access when database is opened next time.

A local temporary table exists only for the duration of a connection or, if defined inside a compound statement, for the duration of the compound statement.

A global temporary table remains in the database permanently, but the rows exist only within a given connection. When connection is closed, the data in the global temporary table disappears. However, the table definition remains with the database for access when database is opened next time.

When SET QUOTED_IDENTIFIER is ON, IDENTIFIERS can be delimited by DOUBLE QUOTATION marks, and literals must be delimited by single quotation marks. When SET QUOTED_IDENTIFIER is OFF, identifiers cannot be quoted and must follow all Transact‐SQL RULES for identifiers.

When SET QUOTED_IDENTIFIER is ON, identifiers can be delimited by double quotation marks, and literals must be delimited by single quotation marks. When SET QUOTED_IDENTIFIER is OFF, identifiers cannot be quoted and must follow all Transact‐SQL rules for identifiers.

ANSWER : SELECT * FROM TABLE1, SELECT COUNT(*) FROM table1, SELECT rows FROM sysindexes WHERE id = OBJECT_ID(table1) AND indid < 2.

Log shipping is the process of automating the backup of database and TRANSACTION log files on a production SQL server, and then restoring them ONTO a STANDBY server. Enterprise Editions only supports log shipping. In log shipping the transactional log file from one server is automatically updated into the backup database on the other servr. If one server fails, the other server will have the same DB and can be used this as the DISASTER Recovery plan. The key feature of log shipping is that it will automatically backup transaction logs throughout the day and automatically resore them on the standby server at defined interval.

Log shipping is the process of automating the backup of database and transaction log files on a production SQL server, and then restoring them onto a standby server. Enterprise Editions only supports log shipping. In log shipping the transactional log file from one server is automatically updated into the backup database on the other servr. If one server fails, the other server will have the same db and can be used this as the Disaster Recovery plan. The key feature of log shipping is that it will automatically backup transaction logs throughout the day and automatically resore them on the standby server at defined interval.

YES.

Because Transact‐SQL supports recursion, you can write stored procedures that call themselves. Recursion can be DEFINED as a method of problem SOLVING wherein the solution is arrived at by repetitively applying it to subsets of the problem. A common application of recursive logic is to perform numeric computations that lend themselves to repetitive evaluation by th same processing STEPS. Stored procedures are nested when one stored PROCEDURE calls another or executes managed code by referencing a CLR routine, type, or aggregate. You can nest stored procedures and managed code references up to 32 levels.

Yes.

Because Transact‐SQL supports recursion, you can write stored procedures that call themselves. Recursion can be defined as a method of problem solving wherein the solution is arrived at by repetitively applying it to subsets of the problem. A common application of recursive logic is to perform numeric computations that lend themselves to repetitive evaluation by th same processing steps. Stored procedures are nested when one stored procedure calls another or executes managed code by referencing a CLR routine, type, or aggregate. You can nest stored procedures and managed code references up to 32 levels.

SQL SERVER agent plays an IMPORTANT role in the day‐to‐day tasks of a database administrator (DBA). It is often overlooked as ONE of the main tools for SQL Server management. Its PURPOSE is to ease the implementation of tasks for the DBA, with its full‐function scheduling engine, which allows you to schedule your own jobs and scripts.

SQL Server agent plays an important role in the day‐to‐day tasks of a database administrator (DBA). It is often overlooked as one of the main tools for SQL Server management. Its purpose is to ease the implementation of tasks for the DBA, with its full‐function scheduling engine, which allows you to schedule your own jobs and scripts.

SELECT SERVERPROPERTY ('productversion'), SERVERPROPERTY ('productlevel'), SERVERPROPERTY ('edition').

SELECT SERVERPROPERTY ('productversion'), SERVERPROPERTY ('productlevel'), SERVERPROPERTY ('edition').

Windows MODE and Mixed Mode ‐ SQL & Windows.

To change authentication mode in SQL Server click Start, PROGRAMS, Microsoft SQL Server and click SQL Enterprise Manager to run SQL Enterprise Manager from the Microsoft SQL Server program GROUP. Select the server then from the Tools menu select SQL Server Configuration PROPERTIES, and choose the Security PAGE.

Windows mode and Mixed Mode ‐ SQL & Windows.

To change authentication mode in SQL Server click Start, Programs, Microsoft SQL Server and click SQL Enterprise Manager to run SQL Enterprise Manager from the Microsoft SQL Server program group. Select the server then from the Tools menu select SQL Server Configuration Properties, and choose the Security page.

SQL Profiler is a graphical tool that allows system administrators to monitor EVENTS in an instance of Microsoft SQL Server. You can capture and save data about each EVENT to a file or SQL Server table to analyze later. For example, you can monitor a PRODUCTION environment to see which stored procedures are hampering performances by executing too slowly.

Use SQL Profiler to monitor only the events in which you are interested. If traces are BECOMING too large, you can filter them based on the information you want, so that only a subset of the event data is collected. Monitoring too many events adds overhead to the server and the monitoring process and can cause the trace file or trace table o grow very large, especially when the monitoring process takes place over a long period of time.

SQL Profiler is a graphical tool that allows system administrators to monitor events in an instance of Microsoft SQL Server. You can capture and save data about each event to a file or SQL Server table to analyze later. For example, you can monitor a production environment to see which stored procedures are hampering performances by executing too slowly.

Use SQL Profiler to monitor only the events in which you are interested. If traces are becoming too large, you can filter them based on the information you want, so that only a subset of the event data is collected. Monitoring too many events adds overhead to the server and the monitoring process and can cause the trace file or trace table o grow very large, especially when the monitoring process takes place over a long period of time.

Properties of Sub‐QUERY

• A sub‐query must be enclosed in the PARENTHESIS,
• A sub‐query must be put in the right hand of the COMPARISON operator and,
• A sub‐query cannot CONTAIN an ORDER‐BY clause,
• A query can contain more than one sub‐query.

Types of Sub‐query

• Single‐row sub‐query, where the sub‐query RETURNS only one row,
• Multiple‐row sub‐query, where the sub‐query returns multiple rows and,
• Multiple column sub‐query, where the sub‐query returns multiple columns.

Properties of Sub‐Query

Types of Sub‐query

They specify a search condition for a GROUP or an aggregate. But the difference is that HAVING can be USED only with the SELECT statement. HAVING is TYPICALLY used in a GROUP BY clause. When GROUP BY is not used, HAVING BEHAVES like a WHERE clause. Having Clause is basically used only with the GROUP BY function in a QUERY whereas WHERE Clause is applied to each row before they are part of the GROUP BY function in a query.

They specify a search condition for a group or an aggregate. But the difference is that HAVING can be used only with the SELECT statement. HAVING is typically used in a GROUP BY clause. When GROUP BY is not used, HAVING behaves like a WHERE clause. Having Clause is basically used only with the GROUP BY function in a query whereas WHERE Clause is applied to each row before they are part of the GROUP BY function in a query.

This COMMAND is basically used when a large PROCESSING of data has occurred. If a large amount of DELETIONS any modification or Bulk Copy into the tables has occurred, it has to UPDATE the indexes to take these changes into account. UPDATE_STATISTICS updates the indexes on these tables ACCORDINGLY.

This command is basically used when a large processing of data has occurred. If a large amount of deletions any modification or Bulk Copy into the tables has occurred, it has to update the indexes to take these changes into account. UPDATE_STATISTICS updates the indexes on these tables accordingly.

Delete command removes the rows from a table based on the condition that we provide with a WHERE clause. Truncate will actually remove all the rows from a table and there will be no data in the table after we RUN the truncate commad.

TRUNCATE

• TRUNCATE is faster and uses fewer system and transaction log resources than DELETE.
• TRUNCATE removes the data by deallocating the data pages USED to store the table’s data, and only the page deallocations are recorded in the transaction log.
• TRUNCATE removes all rows from a table, but the table structure, its columns, constraints, INDEXES and so on, remains. The counter used by an IDENTITY for new rows is reset to the seed for the column.
• You cannot use TRUNCATE TABLE on a table referenced by a FOREIGN KEY constraint. Because TRUNCATE TABLE is not logged, it cannot activate a trigger.
• TRUNCATE cannot be rolled back.
• TRUNCATE is DDL Command.
• TRUNCATE Resets identity of the table.

DELETE

• DELETE removes rows one at a time and records an entry in the transaction log for each deleted row.
• If you want to retain the identity counter, use DELETE instead. If you want to remove table definition and its data, use the DROP TABLE statement.
• DELETE Can be used with or without a WHERE clause
• DELETE Activates Triggers.
• DELETE can be rolled back.
• DELETE is DML Command.
•  DELETE does not reset identity of the table.

Delete command removes the rows from a table based on the condition that we provide with a WHERE clause. Truncate will actually remove all the rows from a table and there will be no data in the table after we run the truncate commad.

TRUNCATE

DELETE

Both primary KEY and UNIQUE key enforces uniqueness of the column on which they are defined. But by DEFAULT primary key creates a clustered index on the column, where are unique creates a nonclustered index by default. Another MAJOR difference is that, primary key doesn't allow NULL's, but unique key allows one NULL only.

Both primary key and unique key enforces uniqueness of the column on which they are defined. But by default primary key creates a clustered index on the column, where are unique creates a nonclustered index by default. Another major difference is that, primary key doesn't allow NULL's, but unique key allows one NULL only.

In OLTP ‐ online transaction PROCESSING systems relational database design use the discipline of data modeling and generally follow the odd RULES of data normalization in order to ensure absolute data integrity. USING these rules complex information is broken down into its most SIMPLE structures (a table) where all of the individual atomic level elements relate to each other and satisfy the normalization rules.

In OLTP ‐ online transaction processing systems relational database design use the discipline of data modeling and generally follow the odd rules of data normalization in order to ensure absolute data integrity. Using these rules complex information is broken down into its most simple structures (a table) where all of the individual atomic level elements relate to each other and satisfy the normalization rules.

• Case sensitivity ‐ A and a, B and b, etc.
• Accent sensitivity ‐ a and á, o and ó, etc.
• KANA Sensitivity ‐ When JAPANESE kana CHARACTERS Hiragana and Katakana are TREATED differently, it is called Kana sensitive.
• Width sensitivity ‐ A single‐byte CHARACTER (half‐width) and the same character represented as a double‐byte character (full‐width) are treated differently than it is width sensitive.

A table can have one of the following index configurations:

• No INDEXES,
• A CLUSTERED index,
• A clustered index and MANY nonclustered indexes,
• A nonclustered index,
• Many nonclustered indexes.

A table can have one of the following index configurations:

A clustered INDEX is a special type of index that reorders the way records in the table are physically stored. Therefore table can have only one clustered index. The leaf nodes of a clustered index contain the data pages.

A non clustered index is a special type of index in which the logical order of the index does not MATCH the physical stored ordr of the rows on disk. The leaf node of a non clustered index does not CONSIST of the data pages. INSTEAD, the leaf nodes contain index rows.

A clustered index is a special type of index that reorders the way records in the table are physically stored. Therefore table can have only one clustered index. The leaf nodes of a clustered index contain the data pages.

A non clustered index is a special type of index in which the logical order of the index does not match the physical stored ordr of the rows on disk. The leaf node of a non clustered index does not consist of the data pages. Instead, the leaf nodes contain index rows.

SQL SERVER RUNS on port 1433. It can be CHANGED from the Network UTILITY TCP/IP properties –> Port number, both on CLIENT and the server.

SQL Server runs on port 1433. It can be changed from the Network Utility TCP/IP properties –> Port number, both on client and the server.

• Subject‐oriented, meaning that the data in the database is organized so that all the data elements relating to the same real‐world event or OBJECT are linked together;
• Time‐variant, meaning that the CHANGES to the data in the database are tracked and recorded so that reports can be produced showing changes verSUS time;
• Non‐volatile, meaning that data in the database is NEVER over‐written or deleted, once committed, the data is STATIC, read‐only, but retained for future reporting.
• INTEGRATED, meaning that the database contains data from most or all of an organization's operational applications, and that this data is made consistent.

Identity (or AutoNumber) is a column that automatically generates numeric values. A start and increment value can be set, but most DBA LEAVE these at 1. A GUID column also generates NUMBERS; the value of this cannot be controlled. Identity/GUID columns do not NEED to be indexed.

Identity (or AutoNumber) is a column that automatically generates numeric values. A start and increment value can be set, but most DBA leave these at 1. A GUID column also generates numbers; the value of this cannot be controlled. Identity/GUID columns do not need to be indexed.

User‐Defined Functions allow defining its own T‐SQL functions that can accept 0 or more parameters and return a single scalar data value or a table data type.

Different Kinds of User‐Defined Functions created are:

Scalar User‐Defined Function:
A Scalar user‐defined function returns one of the scalar data types. Text, ntext, image and timestamp data types are not supported. These are the type of user‐defined functions that most developers are USED to in other programming languages. You pass in 0 to many parameters and you get a return value.

Inline Table‐Value User‐Defined Function
An Inline Table‐Value user‐defined function returns a table data type and is an exceptional alternative to a VIEW as the user‐defined function can pass parameters into a T‐SQL select command and in essence provide us with a parameterized, non‐updateable view of the underlying tables.

Multi‐statement Table‐Value User‐Defined Function
A Multi‐Statement Table‐Value user‐defined function returns a table and is also an exceptional alternative to a view as the function can support multiple T‐SQL statements to build the final result where the view is limited to a single SELECT statement. Also, the ability to pass parameters into a T-SQL select command or a group of them gives us the capability to in essence CREATE a paameterized, non‐updateable view of the data in the underlying tables. Within the create function command you must define the table structure that is being returned. After CREATING this type of user‐defined function, It can be used in the FROM clause of a T‐SQL command unlike the behavior found when using a stored procedure which can also return record sets.

User‐Defined Functions allow defining its own T‐SQL functions that can accept 0 or more parameters and return a single scalar data value or a table data type.

Different Kinds of User‐Defined Functions created are:

Scalar User‐Defined Function:
A Scalar user‐defined function returns one of the scalar data types. Text, ntext, image and timestamp data types are not supported. These are the type of user‐defined functions that most developers are used to in other programming languages. You pass in 0 to many parameters and you get a return value.

Inline Table‐Value User‐Defined Function
An Inline Table‐Value user‐defined function returns a table data type and is an exceptional alternative to a view as the user‐defined function can pass parameters into a T‐SQL select command and in essence provide us with a parameterized, non‐updateable view of the underlying tables.

Multi‐statement Table‐Value User‐Defined Function
A Multi‐Statement Table‐Value user‐defined function returns a table and is also an exceptional alternative to a view as the function can support multiple T‐SQL statements to build the final result where the view is limited to a single SELECT statement. Also, the ability to pass parameters into a T-SQL select command or a group of them gives us the capability to in essence create a paameterized, non‐updateable view of the data in the underlying tables. Within the create function command you must define the table structure that is being returned. After creating this type of user‐defined function, It can be used in the FROM clause of a T‐SQL command unlike the behavior found when using a stored procedure which can also return record sets.

PRIMARY keys are the unique identifiers for each row. They must contain unique values and cannot be null. Due to their importance in relational DATABASES, Primary keys are the most fundamental of all keys and constraints. A table can have only one Primary key.

FOREIGN keys are both a method of ENSURING data integrity and a MANIFESTATION of the relationship between tables.

Primary keys are the unique identifiers for each row. They must contain unique values and cannot be null. Due to their importance in relational databases, Primary keys are the most fundamental of all keys and constraints. A table can have only one Primary key.

Foreign keys are both a method of ensuring data integrity and a manifestation of the relationship between tables.

CROSS JOIN
A cross join that does not have a WHERE clause produces the Cartesian product of the tables involved in the join. The size of a Cartesian product result set is the number of rows in the first table multiplied by the number of rows in the seond table. The common example is when company wants to combine each product with a pricing table to analyze each product at each price.

Inner Join:
A join that displays only the rows that have a match in both joined tables is KNOWN as inner Join. This is the default type of join in the Query and View Designer.

Outer Join:
A join that includes rows even if they do not have related rows in the joined table is an Outer Join. You can create three DIFFERENT outer join to specify the unmatched rows to be included:

Left Outer Join:
In Left Outer Join all rows in the first‐named table i.e. "left" table, which appears leftmost in the JOIN clause are included. Unmatched rows in the right table do not appear.

Right Outer Join:
In Right Outer Join all rows in the second‐named table i.e. "right" table, which appears rightmost in the JOIN clause are included. Unmatched rows in the left table are not included.

Full Outer Join:
In Full Outer Join all rows in all joined tables are included, whether they are matched or not.

SELF Join:
This is a particular case when one table joins to itself, with one or two aliases to avoid confusion. A self join can be of any type, as long as the joined tables are the same. A self join is rather unique in that it involves a relationship with only one table. The common example is when company has a hierarchal reporting structure whereby one member of staff reports to another. Self Join can be Outer Join or Inner Join.

Cross Join
A cross join that does not have a WHERE clause produces the Cartesian product of the tables involved in the join. The size of a Cartesian product result set is the number of rows in the first table multiplied by the number of rows in the seond table. The common example is when company wants to combine each product with a pricing table to analyze each product at each price.

Inner Join:
A join that displays only the rows that have a match in both joined tables is known as inner Join. This is the default type of join in the Query and View Designer.

Outer Join:
A join that includes rows even if they do not have related rows in the joined table is an Outer Join. You can create three different outer join to specify the unmatched rows to be included:

Left Outer Join:
In Left Outer Join all rows in the first‐named table i.e. "left" table, which appears leftmost in the JOIN clause are included. Unmatched rows in the right table do not appear.

Right Outer Join:
In Right Outer Join all rows in the second‐named table i.e. "right" table, which appears rightmost in the JOIN clause are included. Unmatched rows in the left table are not included.

Full Outer Join:
In Full Outer Join all rows in all joined tables are included, whether they are matched or not.

Self Join:
This is a particular case when one table joins to itself, with one or two aliases to avoid confusion. A self join can be of any type, as long as the joined tables are the same. A self join is rather unique in that it involves a relationship with only one table. The common example is when company has a hierarchal reporting structure whereby one member of staff reports to another. Self Join can be Outer Join or Inner Join.

Sub‐queries are often referred to as sub‐selects, as they allow a SELECT statement to be EXECUTED arbitrarily within the body of another SQL statement. A sub‐query is executed by enclosing it in a set of parentheses. Sub‐queries are generally used to return a single ROW as an atomic VALUE, though they may be used to compare values against multiple rows with the IN keyword.

A sub query is a SELECT statement that is nested within another T‐SQL statement. A sub query SELECT statement if executed independently of the T‐SQL statement, in which it is nested, will return a resultset. Meaning a subquery SELECT statement can standalone and is not depended on the statement in which it is nested. A subquery SELECT statement can return any number of values, and can be found in the column list of a SELECT statement, a FROM, GROUP BY, HAVING, and/or ORDER BY clauses of a T‐SQL statement. A Subquery can also be used as a parameter to a function call. BASICALLY a subquery can be used anywhere an expression can be used.

Sub‐queries are often referred to as sub‐selects, as they allow a SELECT statement to be executed arbitrarily within the body of another SQL statement. A sub‐query is executed by enclosing it in a set of parentheses. Sub‐queries are generally used to return a single row as an atomic value, though they may be used to compare values against multiple rows with the IN keyword.

A sub query is a SELECT statement that is nested within another T‐SQL statement. A sub query SELECT statement if executed independently of the T‐SQL statement, in which it is nested, will return a resultset. Meaning a subquery SELECT statement can standalone and is not depended on the statement in which it is nested. A subquery SELECT statement can return any number of values, and can be found in the column list of a SELECT statement, a FROM, GROUP BY, HAVING, and/or ORDER BY clauses of a T‐SQL statement. A Subquery can also be used as a parameter to a function call. Basically a subquery can be used anywhere an expression can be used.

UDF can be USED in the SQL STATEMENTS anywhere in the WHERE/HAVING/SELECT section where as Stored PROCEDURES cannot be. UDF's that return tables can be treated as another ROWSET. This can be used in JOIN's with other tables. Inline UDF's can be thought of as VIEWS that take parameters and can be used in JOINs and other Rowset operations.

UDF can be used in the SQL statements anywhere in the WHERE/HAVING/SELECT section where as Stored procedures cannot be. UDF's that return tables can be treated as another rowset. This can be used in JOIN's with other tables. Inline UDF's can be thought of as views that take parameters and can be used in JOINs and other Rowset operations.

The physical STORAGE of character strings in SQL Server is controlled by collations. A collation specifies the BIT patterns that represent each character and the rules by which characters are SORTED and compared.

The physical storage of character strings in SQL Server is controlled by collations. A collation specifies the bit patterns that represent each character and the rules by which characters are sorted and compared.

Cursor is a DATABASE object used by applications to manipulate data in a set on a row‐by‐row basis, instead of the TYPICAL SQL commands that operate on all the ROWS in the set at one time.

In order to work with a cursor we need to perform some steps in the following order:

• Declare cursor,
• Open cursor,
• Fetch row from the cursor,
• Process FETCHED row,
• Close cursor,
• Deallocate cursor.

Cursor is a database object used by applications to manipulate data in a set on a row‐by‐row basis, instead of the typical SQL commands that operate on all the rows in the set at one time.

In order to work with a cursor we need to perform some steps in the following order:

LINKED Servers is a concept in SQL Server by which we can add other SQL Server to a Group and query both the SQL Server dbs USING T‐SQL STATEMENTS. With a linked server, you can create very clean, easy to follow, SQL statements that ALLOW remote data to be retrieved, joined and combined with LOCAL data. Stored Procedure sp_addlinked server, sp_addlinkedsrvlogin will be used add new Linked Server.

Linked Servers is a concept in SQL Server by which we can add other SQL Server to a Group and query both the SQL Server dbs using T‐SQL Statements. With a linked server, you can create very clean, easy to follow, SQL statements that allow remote data to be retrieved, joined and combined with local data. Stored Procedure sp_addlinked server, sp_addlinkedsrvlogin will be used add new Linked Server.

An index is a physical structure containing pointers to the data. Indices are created in an existing table to locate rows more quickly and efficiently. It is possible to create an index on one or more COLUMNS of a table, and each index is given a name. The users cannot see the indexes; they are just used to speed up QUERIES. Effective indexes are one of the best ways to improve performance in a DATABASE application. A table scan happens when there is no index available to help a query. In a table scan SQL Server examines EVERY row in the table to satisfy the query results. Table scans are sometimes unavoidable, but on large tables, scans have a terrific impact on performance.

An index is a physical structure containing pointers to the data. Indices are created in an existing table to locate rows more quickly and efficiently. It is possible to create an index on one or more columns of a table, and each index is given a name. The users cannot see the indexes; they are just used to speed up queries. Effective indexes are one of the best ways to improve performance in a database application. A table scan happens when there is no index available to help a query. In a table scan SQL Server examines every row in the table to satisfy the query results. Table scans are sometimes unavoidable, but on large tables, scans have a terrific impact on performance.

A simple view can be thought of as a subset of a table. It can be used for retrieving data, as well as updating or deleting rows. Rows updated or DELETED in the view are updated or deleted in the table when the view was created. It should also be noted that as data in the original table changes, so does data in the view, as views are the way to look at part of the original table. The RESULTS of using a view are not permanently stored in the database. The data accessed through a view is actually constructed using STANDARD T‐SQL select COMMAND and can come from ONE to many different base tables or even other views.

A simple view can be thought of as a subset of a table. It can be used for retrieving data, as well as updating or deleting rows. Rows updated or deleted in the view are updated or deleted in the table when the view was created. It should also be noted that as data in the original table changes, so does data in the view, as views are the way to look at part of the original table. The results of using a view are not permanently stored in the database. The data accessed through a view is actually constructed using standard T‐SQL select command and can come from one to many different base tables or even other views.

A trigger is a SQL procedure that initiates an action when an event (INSERT, DELETE or UPDATE) occurs. Triggers are stored in and managed by the DBMS. Triggers are used to maintain the referential integrity of DATA by changing the data in a systematic fashion. A trigger cannot be called or EXECUTED; DBMS AUTOMATICALLY fires the trigger as a result of a data modification to the associated table. Triggers can be viewed as SIMILAR to stored procedures in that both consist of procedural logic that is stored at the database level. Stored procedures, however, are not event‐drive and are not attached to a specific table as triggers. Stored procedures are explicitly executed by invoking a CALL to the procedure while triggers are implicitly executed. In addition, triggers can also execute stored procedures.

Nested Trigger: A trigger can also contain INSERT, UPDATE and DELETE logic WITHIN itself, so when the trigger is fired because of data modification it can also cause another data modification, thereby firing another trigger. A trigger that contains data modification logic within itself is called a nested trigger.

A trigger is a SQL procedure that initiates an action when an event (INSERT, DELETE or UPDATE) occurs. Triggers are stored in and managed by the DBMS. Triggers are used to maintain the referential integrity of data by changing the data in a systematic fashion. A trigger cannot be called or executed; DBMS automatically fires the trigger as a result of a data modification to the associated table. Triggers can be viewed as similar to stored procedures in that both consist of procedural logic that is stored at the database level. Stored procedures, however, are not event‐drive and are not attached to a specific table as triggers. Stored procedures are explicitly executed by invoking a CALL to the procedure while triggers are implicitly executed. In addition, triggers can also execute stored procedures.

Nested Trigger: A trigger can also contain INSERT, UPDATE and DELETE logic within itself, so when the trigger is fired because of data modification it can also cause another data modification, thereby firing another trigger. A trigger that contains data modification logic within itself is called a nested trigger.

A stored procedure is a named GROUP of SQL statements that have been PREVIOUSLY created and stored in the server DATABASE. Stored procedures accept input parameters so that a single procedure can be used over the network by several clients using diferent input data and when the procedure is modified, all clients automatically get the new version. Stored procedures reduce network traffic and IMPROVE PERFORMANCE. Stored procedures can be used to help ensure the integrity of the database.

E.g: sp_helpdb,sp_renamedb,sp_depends etc.

A stored procedure is a named group of SQL statements that have been previously created and stored in the server database. Stored procedures accept input parameters so that a single procedure can be used over the network by several clients using diferent input data and when the procedure is modified, all clients automatically get the new version. Stored procedures reduce network traffic and improve performance. Stored procedures can be used to help ensure the integrity of the database.

E.g: sp_helpdb,sp_renamedb,sp_depends etc.

1NF:Eliminate Repeating Groups

Make a separate table for each set of related attributes,and give each table a primary key.Each field contains at most one value from its attribute domain.

2NF:Eliminate Redundant DATA

If an attribute depends on only part of a multi‐valued key, remove it to a separate table.

3NF:Eliminate Columns Not Dependent On Key

If attributes do not contribute to a description of the key, remove them to a separate table. All attributes must be directly dependent on the primary key.

BCNF:Boyce‐Codd NORMAL Form

If there are non‐trivial dependencies between candidate key attributes,separate them out into distinct tables.

4NF:Isolate Independent Multiple Relationships

No table MAY contain two or more 1:n or n:m relationships that are not directly related.

5NF:Isolate Semantically Related Multiple Relationships:

There may be practical constrains on information that justify separating logically related many‐to‐many relationships.

ONF:Optimal Normal Form

A model limited to only simple(elemental) facts,as expressed in Object Role Model NOTATION.

1NF:Eliminate Repeating Groups

Make a separate table for each set of related attributes,and give each table a primary key.Each field contains at most one value from its attribute domain.

2NF:Eliminate Redundant Data

If an attribute depends on only part of a multi‐valued key, remove it to a separate table.

3NF:Eliminate Columns Not Dependent On Key

If attributes do not contribute to a description of the key, remove them to a separate table. All attributes must be directly dependent on the primary key.

BCNF:Boyce‐Codd Normal Form

If there are non‐trivial dependencies between candidate key attributes,separate them out into distinct tables.

4NF:Isolate Independent Multiple Relationships

No table may contain two or more 1:n or n:m relationships that are not directly related.

5NF:Isolate Semantically Related Multiple Relationships:

There may be practical constrains on information that justify separating logically related many‐to‐many relationships.

ONF:Optimal Normal Form

A model limited to only simple(elemental) facts,as expressed in Object Role Model notation.

De‐normalization is the process of attempting to optimize the performance of a database by ADDING redundant data. It is sometimes necessary because current DBMS's IMPLEMENT the relational model poorly. A true relational DBMS would allow for a fully normalized database at the logical LEVEL, while providing physical storage of data that is tuned for high performance. De‐normalization is a technique to move from HIGHER to lower normal forms of database modeling in ORDER to speed up database access.

De‐normalization is the process of attempting to optimize the performance of a database by adding redundant data. It is sometimes necessary because current DBMS's implement the relational model poorly. A true relational DBMS would allow for a fully normalized database at the logical level, while providing physical storage of data that is tuned for high performance. De‐normalization is a technique to move from higher to lower normal forms of database modeling in order to speed up database access.

Database normalization is a data design and organization process applied to data STRUCTURES based on rules that help building rlational DATABASES. In RELATIONAL database design, the process of ORGANIZING data to minimize redundancy is called normalization. Normalization usually involves dividing a database into two or more tables and defining relationships between the tables. The objective is to isolate data so that ADDITIONS, deletions, and modifications of a field can be made in just one table and then propagated through the rest of the database via the define relationships.

Database normalization is a data design and organization process applied to data structures based on rules that help building rlational databases. In relational database design, the process of organizing data to minimize redundancy is called normalization. Normalization usually involves dividing a database into two or more tables and defining relationships between the tables. The objective is to isolate data so that additions, deletions, and modifications of a field can be made in just one table and then propagated through the rest of the database via the define relationships.

RELATIONAL tables have six properties:

• VALUES are atomic.
• Column values are of the same kind.
• Each row is unique.
• The sequence of columns is INSIGNIFICANT.
• The sequence of rows is insignificant.
• Each column must have a unique NAME.

Relational tables have six properties:

Relational Data Base Management SYSTEMS (RDBMS) are database management systems that maintain data records and INDICES in tables. RELATIONSHIPS may be created and maintained across and among the data and tables. In a relational database, relationships between data items are expressed by means of tables. Inter dependencies among these tables are expressed by data VALUES rather than by pointers. This ALLOWS a high degree of data independence. An RDBMS has the capability to recombine the data items from different files, providing powerful tools for data usage.

Relational Data Base Management Systems (RDBMS) are database management systems that maintain data records and indices in tables. Relationships may be created and maintained across and among the data and tables. In a relational database, relationships between data items are expressed by means of tables. Inter dependencies among these tables are expressed by data values rather than by pointers. This allows a high degree of data independence. An RDBMS has the capability to recombine the data items from different files, providing powerful tools for data usage.

Response.Redirect: This tells the browser that the requested page can be FOUND at a new location. The browser then initiates another request to the new page loading its contents in the browser. This results in two requests by the browser.

Server.Transfer: It transfers execution from the first page to the second page on the server. As far as the browser client is CONCERNED, it made one request and the INITIAL page is the one responding with content. The benefit of this approach is one less round TRIP to the server from the client browser. Also, any posted form variables and query string parameters are AVAILABLE to the second page as well.

Response.Redirect: This tells the browser that the requested page can be found at a new location. The browser then initiates another request to the new page loading its contents in the browser. This results in two requests by the browser.

Server.Transfer: It transfers execution from the first page to the second page on the server. As far as the browser client is concerned, it made one request and the initial page is the one responding with content. The benefit of this approach is one less round trip to the server from the client browser. Also, any posted form variables and query string parameters are available to the second page as well.

The DataGrid control in ASP.NET enables EASY paging of the data. The AllowPaging property of the DataGrid can be set to True to perform paging, ASP.NET automatically PERFORMS paging and provides the hyperlinks to the other pages in different STYLES, based on the property that has been set for PagerStyle.Mode.

The DataGrid control in ASP.NET enables easy paging of the data. The AllowPaging property of the DataGrid can be set to True to perform paging, ASP.NET automatically performs paging and provides the hyperlinks to the other pages in different styles, based on the property that has been set for PagerStyle.Mode.

Data binding is a way used to CONNECT values from a COLLECTION of data (e.g. DataSet) to the controls on a web FORM. The values from the dataset are automatically displayed in the controls without having to write separate code to DISPLAY them.

Data binding is a way used to connect values from a collection of data (e.g. DataSet) to the controls on a web form. The values from the dataset are automatically displayed in the controls without having to write separate code to display them.

• RequiredFieldValidator,
• RANGEVALIDATOR,
• CompareValidator,
• RegularExpressionValidator,
• CustomValidator,
• ValidationSummary.

Code-Behind is a CONCEPT where the contents of a page are in one file and the server-side code is in another page. This allows different people to work on the same page at the same time and also allows either part of the page to be EASILY REDESIGNED, with no CHANGES REQUIRED in the other. An Inherits attribute is added to the @ Page directive to specify the location of the Code-Behind file to the ASP.NET page.

Code-Behind is a concept where the contents of a page are in one file and the server-side code is in another page. This allows different people to work on the same page at the same time and also allows either part of the page to be easily redesigned, with no changes required in the other. An Inherits attribute is added to the @ Page directive to specify the location of the Code-Behind file to the ASP.NET page.