sql servcer interview questions

8/6/2019 SQL Servcer Interview Questions

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ABSRow-level function

that returns anabsolute value.

ALTER COLUMNCommand used to

change a column'ssize or type in atable.

ALTER TABLECommand used tomodify a table'sdefinition.

ANDLogical operatorthat, when used ina WHEREclause,


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means that bothcriteria have to be

met for a row to beincluded in theresult set.

ASC

Function used inORDER BY to put aSQL result set inascending order.

AVGAggregate functionused to average agroup of rowvalues.

BETWEENAn operator used to


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determine whethera value occurs

within a givenrange of values(inclusive); usedwith a WHEREclause.

BIGINTInteger data typethat can storenumbers from -263to 263 - 1.

BINARYData type used tostore strings of bits.

BITData type that


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consumes only asingle bit of

storage.

CASTConversion functionused to change a

data type of acolumn within aquery.

CEILINGRow-level functionthat returns thenext larger integer.

CHAR(size)Character data typeused when thecolumn length is


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known andunvarying.

CHARACTERData type used tostore anycombination of

letters, numbers,and symbols.

CHARINDEXString function thatreturns the startingposition of aspecified pattern.

CHECKIntegrity constraintused to createbounds for a


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column value.

CONSTRAINTSRestrictions thatcan be placed onvalues whencreating database

objects such astables and views.

CONVERTConversion functionused to explicitlyconvert to a givendata type within ina query.

COUNT(*)Function used tocount the total


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number of rows in aresult set.

COUNT(attribute)Group function thatcounts the numberof rows where

attribute is notNULL.

CREATE INDEXCommand used tocreate an index.

CREATE DATABASECommand used tocreate a database.

CREATE SYNONYMCommand used to


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create a synonym.

CREATE TABLECommand used tocreate a table.

CREATE VIEW

Command used tocreate a view.

CROSS JOINA query option usedto generate aCartesian product.

DATEOracle equivalent ofDATETIME .

DATEADD


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Date function thatadds to a specified

part of a date.

DATEDIFFDate function thatreturns the

difference betweentwo dates.

DATEFORMATDate function thatcontrols how SQLServer interpretsdate constants thatare entered fordates.

DATEPARTDate function that


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returns thespecified part of the

date requested.

DATETIMEData type that canbe used for dates.

DAYDate function thatextracts a day froma date.

DECData type; synonymfor DECIMAL datatype.

DECIMALNumeric data type


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whose storage typevaries based on a

specified precision.

DECLARECommand used tocreate variables on

the fly within ascript.

DELETE FROMCommand thatdeletes rows in atable that maysatisfy a givencondition.

DESCFunction used inORDER BY to put a


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SQL result set intodescending order.

DISTINCTResult set functionthat omits rows thatcontain duplicate

data.

DROP COLUMNCommand used todelete a column ina table.

DROP CONSTRAINTCommand used todelete a namedconstraint.

DROP INDEX


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Command used todelete an index.

DROP SYNONYMCommand used todelete a synonym.

DROP TABLECommand used todelete a table.

DROP VIEWCommand used todelete a view.

EXISTSA keyword in a SQLstatement thatreturns true in aWHERE clause if


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the subqueryfollowing it returns

at least one row.

FLOATDecimal data typethat has a precision

of 15 digits.

FLOORRow-level functionwhich returns thenext lower integervalue when anumber containsdecimal places.

GEtdATEDate function thatreturns the current


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system date andtime.

GROUP BYProduces onesummary row forthe aggregate value

of all values for agiven column.

GUIDGlobal uniqueidentifier;UNIQUEIDENTIFIERdata typeguaranteesworldwideuniqueness, evenamongunconnected


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computers.

HAVINGPart of a SQLstatement that isused to determinewhich groups of a

GROUP BY will beincluded in theresult set.

IMAGELarge object binarydata type; used tostore pictures.

INLogical operator fora WHERE clausethat tests for


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inclusion in anamed set.

INTInteger data typethat can storenumbers from -231

to 231 - 1.

INDEX BYCommand used tocreate an index ona table by a certaincolumn value.

INNER JOINCommand used tocombine two tablesin an equi-joinoperation.


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INSERT INTO..

SELECTA way to insertmany rows into anew table at onetime.

INSERTINTO..VALUES

A way to insertvalues into a tableone row at a time.

INSERTCommand thatallows for theaddition of newrows to a table.


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INTEGERNumeric data type

that has no digitsafter the decimalpoint.

INTERSECT

Set operation thatcombines twoqueries such that itreturns all rows thatare the same inboth result sets.

IS NOT NULLFunction that testsfor the NOT NULLcondition.

ISNULL


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Function thatreturns a true value

if a data itemcontains a null.

JOINCommand used to

join two tables;synonymous withINNER JOIN.

LEFTString function thatreturns the leftportion of a stringup to a givennumber ofcharacters.

LEFT JOIN


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Same as LEFTOUTER JOIN .

LEFT OUTER JOINA join where all therows from the first(left) table are kept

in the result set,regardless ofwhether they havematching rows inthe second (right)table.

LENString function thatreturns the lengthof a string.

LIKE


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A WHERE clauseoption that matches

a particular pattern.

LONGOracle equivalent ofTEXT data type.

LOWERString function usedto convert a stringto lowercase.

LTRIMString function thatremoves blanks orother namedcharacter from thebeginning of astring.


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MAX

Aggregate functionthat returns thehighest of all valuesfrom a column in aset of rows.

MINAggregate functionthat returns thelowest of all valuesfrom a column in aset of rows.

MINUSSet operation thatreturns only thoserows from theresult of the first


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query that are notin the result of the

second query; notavailable in SQLServer.

MONEY

Data type used withcurrency data.

MONTHDate function thatextracts the monthfrom a date.

NATIONALCHARACTER

A data type;synonym forNCHAR data type.


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NCHAR

Fixed-lengthUnicode characterdata type.

NOT

Operator thatreverses the effectof any logicaloperator such asIN, LIKE, andEXISTS.

NOT BETWEENOperator thatallows you todetermine whethera value does notoccur within a given


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range of values.

NOT EXISTSOperator thatreturns true in aWHERE clause ifthe subquery

following it returnsno rows.

NOT NULLOperator thatreturns true if anattribute has a non-null value.

NOT NULLConstraintIntegrity constraintthat denies the


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creation of a rowwhen an attribute

has a null value.

NULLValue that isunknown.

NULLIFFunction thatreturns a NULL if acertain condition ismet in anexpression.

NUMERICSynonym forDECIMAL data type.

NVARCHAR


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Variable-lengthUnicode character

data type.

ORBinary logicaloperator that

returns a true valueif either one of theexpressions is true.

ORDER BYClause that sortsthe results of aquery before theyare displayed.

OUTER JOINJoin where rowsfrom a table are


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kept in the resultset although there

is no matching rowin the other tableused in the join.

PERCENT

Function that isused to return acertain percentageof records that fallat the top of arange specified.

PRIMARY KEYConstraint used tocreate a primarykey in a table; usedin CREATE TABLEand ALTER TABLE


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commands.

REALDecimal data typethat has a precisionof seven digits.

REFERENCESConstraint part thatdefines the tablename and key usedto referenceanother table.

RIGHTString function thatreturns the rightportion of a string.

RIGHT JOIN


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Same as RIGHTOUTER JOIN .

RIGHT OUTER JOINJoin where all therows from thesecond (right)

relation are keptwhether matched ornot in a joinoperation.

ROUNDFunction used toround numbers to aspecified number ofdecimal places.

ROWCOUNT(n)Function that


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returns the first nrows.

RTRIMString function thatremoves blanksfrom the right end

of a string.

SELECTCommand thatallows you toretrieve rows fromtables (or views) ina database.

SETCommand used toassign values tovariables.


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SET DATEFORMAT

Date function usedto change theformat in whichSQL Server reads indates.

SMALLDATETIMEData type used tostore dates.

SMALLINTInteger data typethat can storenumbers between -215 to 215 - 1.

SMALLMONEYData type that can


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be used withcurrency data.

SQUARERow-level functionthat returns thesquare of a

number.

SQL_VARIANTData type used tostore values of anydata type exceptTEXT or IMAGE.

SQRTRow-level functionthat returns thesquare root ofpositive numeric


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values.

STRConversion functionthat alwaysconverts from anumber to a

character data type.

SUBSTRINGString function thatreturns part of astring.

SUMGroup function thatadds up all thevalues for a columnvalue in a set ofrows.


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TABLE

A two-dimensional(row by column)arrangement ofdata.

TEXTCharacter largeobject data type.

TINYINTInteger data typethat can storenumbers between 0and 255.

TOPFunction thatreturns a specified


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number of recordsfrom the top of a

result set.

UNIONSet operation thatcombines two

queries such that itreturns all distinctrows for the resultsets of bothqueries. The twoqueries must haveunion-compatibleresult sets.

UNION ALLSet operation thatcombines twoqueries and returns


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all rows from boththe SELECT

statements(queries). A UNION

ALL also includesduplicate rows. Thetwo queries must

have union-compatible resultsets.

UNIQUEIntegrity constraintthat disallowsduplicate entries foran attribute eventhough the columnis not a primarykey.


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UNIQUEIDENTIFIERData type that

guaranteesuniqueness of theidentifier, evenamongunconnected

computers.

UPDATECommand thatchanges values inspecified columns inspecified tables .

UPPERString function usedto display all outputin uppercase.


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USECommand used to

open a database.

UUIDUniversal uniqueidentifier; the

UNIQUEIDENTIFIERdata type thatguaranteesuniqueness, evenamongunconnectedcomputers.

VARBINARYData type used tostore variable-length binary data.


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VARCHAR

Character data typeused when the fieldlength is varying.

VARCHAR2

Oracle equivalent ofVARCHAR.

WHERERow filter part of aSQL statement thatallows you tospecify criteria oncolumn values forrows that are beingselected from atable.


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WITH TIESClause used with

the TOP function toretrieve rows thatare ties.

XML

A new SQL Serverdata type used tomodel complexdata.

YEARDate function thatextracts the yearfrom a date.

21-03-09, 09:08 #2 (permalink)


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PM

teja83Senior Member

Join Date: Dec

2008

Posts: 221

Miscellaneous

SQL Server

Objects

y Synonyms

A synonym isan alternative

name for a

schema-scoped

object. It is asingle-partname to

reference a

base object. A

synonym issimilar to an

alias, but it


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replaces a

two-part,

three-part, orfour-part

name.

y Databasediagrams

A databasediagram is a

graphical

design of atable or set of

tables that

can be usedto illustrate

the tables and

relationshipswithin a

database.

y Statistics


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Stored within

a table,

statistics areautomatically

created andoptionally

supplemented

histograms.y AssembliesAn assembly

references amanaged

application

module (DLLfile) that was

created in the

.NETFramework

common

language


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runtime

(CLR).y ProxiesIn the msdb

context, aproxy defines

security

context andprovides the

SQL Server

Agent accessto credentials

for a Windows

user.

Read more:

http://www.placementpapers.us/sql_ser

ver/905-


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