Selection sort C C++ source code

Selection sort C C++ source code
//selection sort
#include <iostream.h>
void selectionSort(int *array,int length)//selection sort function 
    int i,j,min,minat;

      for(j=i+1;j<(length);j++) //select the min of the rest of array
          if(min>array[j])   //ascending order for descending reverse
              minat=j;  //the position of the min element 
      int temp=array[i] ;
      array[i]=array[minat];  //swap 

void printElements(int *array,int length) //print array elements
    int i=0;
void main()

    int a[]={9,6,5,23,2,6,2,7,1,8};   // array to sort 
    selectionSort(a,10);                 //call to selection sort  
    printElements(a,10);               // print elements 

Java iterate through map, hashmap - working source code

Iterating through Map in Java - working efficient source code 

Map<String, Object> map = ...;

The solution uses map.keySet(), map.values(), and map.entrySet().

Text Prompted Remote Speaker Authentication : Joint Speech and Speaker Recognition/Verification System :: Major Project ::: Introduction

Biometrics is, in the simplest definition, something you are. It is a physical characteristic unique to each individual such as fingerprint, retina, iris, speech. Biometrics has a very useful application in security; it can be used to authenticate a person’s identity and control access to a restricted area, based on the premise that the set of these physical characteristics can be used to uniquely identify individuals.

Speech signal conveys two important types of information, the primarily the speech content and on the secondary level, the speaker identity. Speech recognizers aim to extract the lexical information from the speech signal independently of the speaker by reducing the inter-speaker variability. On the other hand, speaker recognition is concerned with extracting the identity of the person speaking the utterance. So both speech recognition and speaker recognition system is possible from same voice input.

Desired Output of the Combined System
Text Prompted Remote Speaker Authentication is a voice biometric system that authenticates a user before permitting the user to log into a system on the basis of the user’s input voice. It is a web application. Voice signal acquisition and feature extraction is done on the client. Training and Authentication task based on the voice feature obtained from client side is done on Server. The authentication task is based on text-prompted version of speaker recognition, which incorporates both speaker recognition and speech recognition. This joint implementation of speech and speaker recognition includes text-independent speaker recognition and speaker-independent speech recognition. Speaker Recognition verifies whether the speaker is claimed one or not while Speech Recognition verifies whether or not spoken word matches the prompted word.

java calculate method run time

long startTime = System.currentTimeMillis();

doReallyLongThing(); // call your method here
long endTime = System.currentTimeMillis();
// calculate the difference - that the method just took to executeSystem.out.println("That took " + (endTime - startTime) + " milliseconds");

SQL basics- complete reference guide - part8 SQL System Commands

Part8: SQL System Commands Reference guide

ARRAY_GETReturns one element of an array.ARRAY_GET(arrayExpression, indexExpression)
ARRAY_LENGTHReturns the length of an array.ARRAY_GET(arrayExpression)
AUTOCOMMITReturns true if auto commit is switched on for this session.AUTOCOMMIT()
CANCEL_SESSIONCancels the currently executing statement of another session.CANCEL_SESSION(sessionInt)
CASEWHEN FunctionReturns 'a' if the boolean expression is true, otherwise 'b'.CASEWHEN(boolean, aValue, bValue)
CASTConverts a value to another data type.CAST(value AS dataType)
COALESCEReturns the first value that is not null.COALESCE(aValue, bValue [,...])
CONVERTConverts a value to another data type.CONVERT(value, dataType)
CURRVALReturns the current (last) value of the sequence, independent of the session.CURRVAL( [ schemaName, ] sequenceString )
CSVREADReturns the result set of reading the CSV (comma separated values) file.CSVREAD(fileNameString [, columnsString [, csvOptions ] ] )
CSVWRITEWrites a CSV (comma separated values).CSVWRITE ( fileNameString, queryString [, csvOptions [, lineSepString] ] )
DATABASEReturns the name of the database.DATABASE()
DATABASE_PATHReturns the directory of the database files and the database name, if it is file
FILE_READReturns the contents of a file.FILE_READ(fileNameString [,encodingString])
GREATESTReturns the largest value that is not NULL, or NULL if all values are NULL.GREATEST(aValue, bValue [,...])
IDENTITYReturns the last inserted identity value for this session.IDENTITY()
IFNULLReturns the value of 'a' if it is not null, otherwise 'b'.IFNULL(aValue, bValue)
LEASTReturns the smallest value that is not NULL, or NULL if all values are NULL.LEAST(aValue, bValue [,...])
LOCK_MODEReturns the current lock mode.LOCK_MODE()
LOCK_TIMEOUTReturns the lock timeout of the current session (in milliseconds).LOCK_TIMEOUT()
LINK_SCHEMACreates table links for all tables in a schema.LINK_SCHEMA(targetSchemaString, driverString, urlString,
userString, passwordString, sourceSchemaString)
MEMORY_FREEReturns the free memory in KB (where 1024 bytes is a KB).MEMORY_FREE()
MEMORY_USEDReturns the used memory in KB (where 1024 bytes is a KB).MEMORY_USED()
NEXTVALReturns the next value of the sequence.NEXTVAL ( [ schemaName, ] sequenceString )
NULLIFReturns NULL if 'a' is equals to 'b', otherwise 'a'.NULLIF(aValue, bValue)
READONLYReturns true if the database is read-only.READONLY()
ROWNUMReturns the number of the current row.ROWNUM()
SCHEMAReturns the name of the default  schema for this session.SCHEMA()
SCOPE_IDENTITYReturns the last inserted identity value for this session for the current scope.SCOPE_IDENTITY()
SESSION_IDReturns the unique session id number for the current database connection.SESSION_ID()
SETUpdates a variable with the given value.SET(@variableName, value)
TABLEReturns the result set.{ TABLE | TABLE_DISTINCT } ( { name dataType = expression } [,...] )
TRANSACTION_IDReturns the current transaction id for this session.TRANSACTION_ID()
USERReturns the name of the current user of this session.{ USER | CURRENT_USER } ()Select User();

SQL basics- complete reference guide - part7 - Date Time Functions

Part7: SQL Date Time Functions Reference

CURRENT_DATEReturns the current date.{ CURRENT_DATE [ () ] | CURDATE() | SYSDATE | TODAY }
CURRENT_TIMEReturns the current time.{ CURRENT_TIME [ () ] | CURTIME() }
CURRENT_TIMESTAMPReturns the current timestamp.{ CURRENT_TIMESTAMP [ ( [ int ] ) ] | NOW( [ int ] ) }
DATEADDAdds units to a timestamp.DATEADD(unitString, addInt, timestamp)
DATEDIFFReturns the the number of crossed unit boundaries between two timestamps.{ DATEDIFF | TIMESTAMPDIFF } (unitString, aTimestamp, bTimestamp)
DAYNAMEReturns the name of the day (in English).DAYNAME(date)
DAY_OF_MONTHReturns the day of the month (1-31).DAY_OF_MONTH(date)
DAY_OF_WEEKReturns the day of the week (1 means Sunday).DAY_OF_WEEK(date)
DAY_OF_YEARReturns the day of the year (1-366).DAY_OF_YEAR(date)
EXTRACTReturns a specific value from a timestamps.EXTRACT ( { YEAR | YY | MONTH | MM | DAY | DD | DAY_OF_YEAR
    FROM timestamp )
FORMATDATETIMEFormats a date, time or timestamp as a string.FORMATDATETIME ( timestamp, formatString
[ , localeString [ , timeZoneString ] ] )
HOURReturns the hour (0-23) from a timestamp.HOUR(timestamp)
MINUTEReturns the minute (0-59) from a timestamp.MINUTE(timestamp)
MONTHReturns the month (1-12) from a timestamp.MONTH(timestamp)
MONTHNAMEReturns the name of the month (in English).MONTHNAME(date)
PARSEDATETIMEParses a string and returns a timestamp.PARSEDATETIME(string, formatString
[, localeString [, timeZoneString]])
QUARTERReturns the quarter (1-4) from a timestamp.QUARTER(timestamp)
SECONDReturns the second (0-59) from a timestamp.SECOND(timestamp)
WEEKReturns the week (1-53) from a timestamp.WEEK(timestamp)
YEARReturns the year from a timestamp.YEAR(timestamp)

Java Capture/save image from swing Component eg : JFrame JPanel ..

Capture image from any swing Component and save to file.
Capture  :
BufferedImage image = new BufferedImage(component.getWidth(),
                                     component.getHeight(), BufferedImage.TYPE_INT_RGB);
// paints into image's Graphics
Save Image :

SQL basics- complete reference guide - part6 - String functions

Part6: SQL String Functions Complete Reference

ASCIIReturns the ASCII value of the first character in the string.ASCII(string)
BIT_LENGTHReturns the number of bits in a string.BIT_LENGTH(string)
LENGTHReturns the number of characters in a string.{ LENGTH | CHAR_LENGTH | CHARACTER_LENGTH } ( string )
OCTET_LENGTHReturns the number of bytes in a string.OCTET_LENGTH(string)
CHARReturns the character that represents the ASCII value.{ CHAR | CHR } ( int )
CONCATCombines strings.CONCAT(string, string [,...])
DIFFERENCEReturns the difference between the sounds of two strings.DIFFERENCE(string, string)
HEXTORAWConverts a hex representation of a string to a string.HEXTORAW(string)
RAWTOHEXConverts a string to the hex representation.RAWTOHEX(string)
INSTRReturns the location of a search string in a string.INSTR(string, searchString, [, startInt])
INSERT FunctionInserts a additional string into the original string at a specified start position.INSERT(originalString, startInt, lengthInt, addString)
LOWERConverts a string to lowercase.{ LOWER | LCASE } ( string )
UPPERConverts a string to uppercase.{ UPPER | UCASE } ( string )
LEFTReturns the leftmost number of characters.LEFT(string, int)
RIGHTReturns the rightmost number of characters.RIGHT(string, int)
LOCATEReturns the location of a search string in a string.LOCATE(searchString, string [, startInt])
POSITIONReturns the location of a search string in a string.POSITION(searchString, string)
LPADLeft pad the string to the specified length.LPAD(string, int[, paddingString])
RPADRight pad the string to the specified length.RPAD(string, int[, paddingString])
LTRIMRemoves all leading spaces from a string.LTRIM(string)
RTRIMRemoves all trailing spaces from a string.RTRIM(string)
TRIMRemoves all leading spaces, trailing spaces, or spaces at both ends, from a string.TRIM ( [ { LEADING | TRAILING | BOTH } [ string ] FROM ] string )
REGEXP_REPLACEReplaces each substring that matches a regular expression.REGEXP_REPLACE(inputString, regexString, replacementString)
REPEATReturns a string repeated some number of times.REPEAT(string, int)
REPLACEReplaces all occurrences of a search string in a text with another string.REPLACE(string, searchString [, replacementString])
SOUNDEXReturns a four character code representing the sound of a string.SOUNDEX(string)
SPACEReturns a string consisting of a number of spaces.SPACE(int)
STRINGDECODEConverts a encoded string using the Java string literal encoding format.STRINGDECODE(string)
STRINGENCODEEncodes special characters in a string using the Java string literal encoding format.STRINGENCODE(string)
STRINGTOUTF8Encodes a string to a byte array using the UTF8 encoding format.STRINGTOUTF8(string)
SUBSTRINGReturns a substring of a string starting at a position.{ SUBSTRING | SUBSTR } ( string, startInt [, lengthInt ] )
UTF8TOSTRINGDecodes a byte array in the UTF8 format to a string.UTF8TOSTRING(bytes)
XMLATTRCreates an XML attribute element of the form "name=value".XMLATTR(nameString, valueString)
XMLNODECreate an XML node element.XMLNODE(elementString [, attributesString [, contentString]])
XMLCOMMENTCreates an XML comment.XMLCOMMENT(commentString)
XMLCDATACreates an XML CDATA element.XMLCDATA(valueString)
XMLTEXTCreates an XML text element.XMLTEXT(valueString)

java pad string left right - String.format() method

String.format() can be used to left/right pad a given string.
public static String padRight(String s, int n) {
     return String.format("%1$-" + n + "s", s);  }
public static String padLeft(String s, int n) {
    return String.format("%1$#" + n + "s", s);  }
public static void main(String args[]) throws Exception {
 System.out.println(padRight("Howto", 20) + "*");
 System.out.println(padLeft("Howto", 25) + "*");

Top Java Interview Question : reverse a string using recursion

Best Answer using Recursion :

  public String reverse(String str) {
     if ((null == str) || (str.length()  <= 1)) {
        return str;
    return reverse(str.substring(1)) + str.charAt(0);

Less Best Answer :
public class JdkReverser implements Reverser {
  public String reverse(String str) {
     if ((null == str) || (str.length() <= 1)) {
         return str;
     return new StringBuffer(str).reverse().toString();

SQL basics- complete reference guide - part5 - Mathematical Functions

Part5: Mathematical Functions in SQL- Complete Reference

ABSABS ( { int | long | decimal | double } )
ATAN2ATAN2(double, double)
BITANDThe bitwise AND operation.BITAND(long, long)
BITORThe bitwise OR operation.BITOR(long, long)
BITXORThe bitwise XOR operation.BITXOR(long, long)
MODThe modulo operation.MOD(long, long)
POWERPOWER(double, double)
RANDCalling the function without parameter returns the next a pseudo random number.RAND( [ int ] )
RANDOM_UUIDReturns a new UUID with 122 pseudo random bits.RANDOM_UUID()
ROUNDRounds to a number of digits.ROUND(double, digitsInt)
ROUNDMAGICThis function rounds numbers in a good way, but it is slow.ROUNDMAGIC(double)
SECURE_RANDGenerates a number of cryptographically secure random numbers.SECURE_RAND(int)
SIGNReturns -1 if the value is smaller 0, 0 if zero, and otherwise 1.SIGN ( { int | long | decimal | double } )
ENCRYPTEncrypts data using a key.ENCRYPT(algorithmString, keyBytes, dataBytes)
DECRYPTDecrypts data using a key.DECRYPT(algorithmString, keyBytes, dataBytes)
HASHCalculate the hash value using an algorithm, and repeat this process for a number of iterations.HASH(algorithmString, dataBytes, iterationInt)
TRUNCATETruncates to a number of digits (to the next value closer to 0).TRUNCATE(double, digitsInt)
COMPRESSCompresses the data using the specified compression algorithm.COMPRESS(dataBytes [, algorithmString])
EXPANDExpands data that was compressed using the COMPRESS function.EXPAND(bytes)
ZEROReturns the value 0.ZERO()

SQL basics- complete reference guide - part4 - Aggregate Functions in SQL

Part4: Aggregate Functions in SQL- complete reference sheet

AVGThe average (mean) value.AVG ( [ DISTINCT ] { int | long | decimal | double } )
BOOL_ANDReturns true if all expressions are true.BOOL_AND(boolean)
BOOL_ORReturns true if any expression is true.BOOL_OR(boolean)
COUNTThe count of all row, or of the non-null values.COUNT( { * | { [ DISTINCT ] expression } } )
GROUP_CONCATConcatenates strings with a separator.GROUP_CONCAT ( [ DISTINCT ] string
[ ORDER BY { expression [ ASC | DESC ] } [,...] ]
[ SEPARATOR expression ] )
MAXThe highest value.MAX(value)
MINThe lowest value.MIN(value)
SUMThe sum of all values.SUM( [ DISTINCT ] { int | long | decimal | double } )
SELECTIVITYEstimates the selectivity (0-100) of a value.SELECTIVITY(value)
STDDEV_POPThe population standard deviation.STDDEV_POP( [ DISTINCT ] double )
STDDEV_SAMPThe sample standard deviation.STDDEV_SAMP( [ DISTINCT ] double )
VAR_POPThe population variance (square of the population standard deviation).VAR_POP( [ DISTINCT ] double )
VAR_SAMPThe sample variance (square of the sample standard deviation).VAR_SAMP( [ DISTINCT ] double )

Call one constructor from another in Java

Is this possible to call one constructor from another in Java ?

Yes, it is possible:

public class Foo
    private int x;

    public Foo()
        this(1);//calling constructor -->> public Foo(int x)

    public Foo(int x)
        this.x = x;

SQL basics- complete reference guide - part3 - Data Types in SQL

Part3: SQL Data Types Reference

INT TypePossible values: -2147483648 to 2147483647.INT | INTEGER | MEDIUMINT | INT4 | SIGNED
BOOLEAN TypePossible values: TRUE and FALSE.BOOLEAN | BIT | BOOL
TINYINT TypePossible values are: -128 to 127.TINYINT
SMALLINT TypePossible values: -32768 to 32767.SMALLINT | INT2 | YEAR
BIGINT TypePossible values: -9223372036854775808 to 9223372036854775807.BIGINT | INT8
IDENTITY TypeAuto-Increment value.IDENTITY
DECIMAL TypeData type with fixed precision and scale.{ DECIMAL | NUMBER | DEC | NUMERIC } ( precisionInt [ , scaleInt ] )
DOUBLE TypeFloating point number.{ DOUBLE [ PRECISION ] | FLOAT | FLOAT4 | FLOAT8 }
REAL TypeSingle precision floating point number.REAL
TIME TypeThe format is hh:mm:ss.TIME
DATE TypeThe format is yyyy-MM-dd.DATE
TIMESTAMP TypeThe format is yyyy-MM-dd hh:mm:ss[.{ TIMESTAMP | DATETIME | SMALLDATETIME }
BINARY TypeRepresents a byte array.{ BINARY | VARBINARY | LONGVARBINARY | RAW | BYTEA } [ ( precisionInt ) ]
OTHER TypeThis type allows storing serialized Java objects.OTHER
    | NVARCHAR2 | VARCHAR_CASESENSITIVE}  [ ( precisionInt ) ]
VARCHAR_IGNORECASE TypeSame as VARCHAR, but not case sensitive when comparing.VARCHAR_IGNORECASE [ ( precisionInt ) ]
CHAR TypeThis type is supported for compatibility with other databases and older
{ CHAR | CHARACTER | NCHAR } [ ( precisionInt ) ]
BLOB TypeLike BINARY, but intended for very large values such as files or images.{ BLOB | TINYBLOB | MEDIUMBLOB | LONGBLOB | IMAGE | OID } [ ( precisionInt ) ]
CLOB TypeCLOB is like VARCHAR, but intended for very large values.{ CLOB | TINYTEXT | TEXT | MEDIUMTEXT | LONGTEXT | NTEXT | NCLOB } [ ( precisionInt ) ]
UUID TypeUniversally unique identifier.UUID
ARRAY TypeAn array of values.ARRAY

SQL basics- complete reference guide - part2 - DDL

Part2: DDL -Data Definition Language Reference

ALTER INDEX RENAMERenames an index.ALTER INDEX indexName RENAME TO newIndexName
ALTER SCHEMA RENAMERenames a schema.ALTER SCHEMA schema RENAME TO newSchemaName
ALTER SEQUENCEChanges the next value and the increment of a sequence.ALTER SEQUENCE sequenceName [ RESTART WITH long ] [ INCREMENT BY long ]
ALTER TABLE ADDAdds a new column to a table.ALTER TABLE tableName ADD name dataType [ DEFAULT expression ]
ALTER TABLE ADD CONSTRAINTAdds a constraint to a table.ALTER TABLE tableName ADD constraint [ CHECK | NOCHECK ]
ALTER TABLE ALTERChanges the data type of a column, rename a column,
change the identity value, or change the selectivity.
{ { dataType [ DEFAULT expression ] [ [ NOT ] NULL ] [ AUTO_INCREMENT | IDENTITY ] }
    | { RENAME TO name }
    | { RESTART WITH long }
    | { SELECTIVITY int }
    | { SET DEFAULT expression }
    | { SET NULL }
    | { SET NOT NULL } }
ALTER TABLE DROP COLUMNRemoves a column from a table.ALTER TABLE tableName DROP COLUMN columnName
ALTER TABLE DROP CONSTRAINTRemoves a constraint or a primary key from a table.ALTER TABLE tableName DROP { CONSTRAINT [ IF EXISTS ] constraintName | PRIMARY KEY }
ALTER TABLE SETDisables or enables referential integrity checking for a table.ALTER TABLE tableName SET REFERENTIAL_INTEGRITY
ALTER USER ADMINSwitches the admin flag of a user on or off.ALTER USER userName ADMIN { TRUE | FALSE }
ALTER USER RENAMERenames a user.ALTER USER userName RENAME TO newUserName
ALTER USER SET PASSWORDChanges the password of a user.ALTER USER userName SET { PASSWORD string | SALT bytes HASH bytes }
ALTER VIEWRecompiles a view after the underlying tables have been changed or created.ALTER VIEW viewName RECOMPILE
ANALYZEUpdates the selectivity statistics of all tables.ANALYZE [ SAMPLE_SIZE rowCountInt ]
COMMENTSets the comment of a database object.COMMENT ON
{ { COLUMN [ schemaName. ] tableName.columnName }
    | SCHEMA | SEQUENCE | TRIGGER | USER | DOMAIN } [ schemaName. ] objectName } }
IS expression
CREATE AGGREGATECreates a new user-defined aggregate function.CREATE AGGREGATE [ IF NOT EXISTS ] newAggregateName FOR className
CREATE ALIASCreates a new function alias.CREATE ALIAS [ IF NOT EXISTS ] newFunctionAliasName [ DETERMINISTIC ]
{ FOR classAndMethodName | AS sourceCodeString }
CREATE CONSTANTCreates a new constant.CREATE CONSTANT [ IF NOT EXISTS ] newConstantName VALUE expression
CREATE DOMAINCreates a new data type (domain).CREATE DOMAIN [ IF NOT EXISTS ] newDomainName AS dataType
[ DEFAULT expression ] [ [ NOT ] NULL ] [ SELECTIVITY selectivity ]
[ CHECK condition ]
CREATE INDEXCreates a new index.CREATE { [ UNIQUE ] [ HASH ] INDEX [ IF NOT EXISTS ] newIndexName
    | PRIMARY KEY [ HASH ] }
ON tableName ( indexColumn [,...] )
name ( driverString, urlString, userString, passwordString,
[ originalSchemaString, ] originalTableString ) [ EMIT UPDATES | READONLY ]
CREATE ROLECreates a new role.CREATE ROLE [ IF NOT EXISTS ] newRoleName
CREATE SCHEMACreates a new schema.CREATE SCHEMA [ IF NOT EXISTS ] name [ AUTHORIZATION ownerUserName ]
CREATE SEQUENCECreates a new sequence.CREATE SEQUENCE [ IF NOT EXISTS ] newSequenceName [ START WITH long ]
[ INCREMENT BY long ] [ CACHE long ]
{ { ( { columnDefinition | constraint } [,...] ) [ AS select ] }
    | { AS select } }
[ QUEUE int ] [ NOWAIT ] CALL triggeredClassName
CREATE USERCreates a new user.CREATE USER [ IF NOT EXISTS ] newUserName
{ PASSWORD string | SALT bytes HASH bytes } [ ADMIN ]
CREATE VIEWCreates a new view.CREATE [ OR REPLACE ] [ FORCE ] VIEW [ IF NOT EXISTS ] newViewName
[ ( columnName [,...] ) ] AS select
DROP AGGREGATEDrops an existing user-defined aggregate function.DROP AGGREGATE [ IF EXISTS ] aggregateName
DROP ALIASDrops an existing function alias.DROP ALIAS [ IF EXISTS ] existingFunctionAliasName
DROP ALL OBJECTSDrops all existing views, tables, sequences, schemas, function aliases, roles,
user-defined aggregate functions, domains, and users (except the current user).
DROP CONSTANTDrops a constant.DROP CONSTANT [ IF EXISTS ] constantName
DROP DOMAINDrops a data type (domain).DROP DOMAIN [ IF EXISTS ] domainName
DROP INDEXDrops an index.DROP INDEX [ IF EXISTS ] indexName
DROP ROLEDrops a role.DROP ROLE [ IF EXISTS ] roleName
DROP SCHEMADrops a schema.DROP SCHEMA [ IF EXISTS ] schemaName
DROP SEQUENCEDrops a sequence.DROP SEQUENCE [ IF EXISTS ] sequenceName
DROP TABLEDrops an existing table, or a list of tables.DROP TABLE [ IF EXISTS ] tableName [,...] [ CASCADE | RESTRICT ]
DROP TRIGGERDrops an existing trigger.DROP TRIGGER [ IF EXISTS ] triggerName
DROP USERDrops a user.DROP USER [ IF EXISTS ] userName
DROP VIEWDrops an existing view.DROP VIEW [ IF EXISTS ] viewName [ RESTRICT | CASCADE ]
TRUNCATE TABLERemoves all rows from a table.TRUNCATE TABLE tableName

SQL basics- complete reference guide - part1 - DML

Part1: DML-Data Manipulation Language

SELECTSelects data from a table or multiple tables.SELECT [ TOP term ] [ DISTINCT | ALL ] selectExpression [,...]
FROM tableExpression [,...] [ WHERE expression ]
[ GROUP BY expression [,...] ] [ HAVING expression ]
[ { UNION [ ALL ] | MINUS | EXCEPT | INTERSECT } select ] [ ORDER BY order [,...] ]
[ LIMIT expression [ OFFSET expression ] [ SAMPLE_SIZE rowCountInt ] ]
INSERTInserts a new row / new rows into a table.INSERT INTO tableName [ ( columnName [,...] ) ]
{ VALUES { ( { DEFAULT | expression } [,...] ) } [,...] | [ DIRECT ] [ SORTED ] select }
UPDATEUpdates data in a table.UPDATE tableName [ [ AS ] newTableAlias ]
SET { columnName= { DEFAULT | expression } } [,...]
[ WHERE expression ]
DELETEDeletes rows form a table.DELETE FROM tableName [ WHERE expression ]
BACKUPBacks up the database files to a .BACKUP TO fileNameString
CALLCalculates a simple expression.CALL expression
EXPLAINShows the execution plan for a statement.EXPLAIN { [ PLAN FOR ] | ANALYZE } { select | insert | update | delete | merge }
MERGEUpdates existing rows, and insert rows that don't exist.MERGE INTO tableName [ ( columnName [,...] ) ]
[ KEY ( columnName [,...] ) ]
{ VALUES { ( { DEFAULT | expression } [,...] ) } [,...] | select }
RUNSCRIPTRuns a SQL script from a file.RUNSCRIPT FROM fileNameString [ scriptCompression ]
[ CIPHER cipher PASSWORD string ] [ CHARSET charsetString ]
SCRIPTCreates a SQL script from the database.SCRIPT [ SIMPLE ] [ NODATA ] [ NOPASSWORDS ] [ NOSETTINGS ]
[ DROP ] [ BLOCKSIZE blockSizeInt ]
[ TO fileNameString [ scriptCompression ]
    [ CIPHER cipher PASSWORD string ] ]
[ CHARSET charsetString ]
SHOWLists the schemas, tables, or the columns of a table.SHOW { SCHEMAS | TABLES [ FROM schemaName ] |
    COLUMNS FROM tableName [ FROM schemaName ] }

Scenarios in which Serialization cannot happen

What are the special cases in which serialization cannot happen?
-> There are following scenarios in which serialization cannot happen:
a. Variables are transient.
b. Variables are static.
c. Base class variables are serialized if class itself is serializable.

java prevent sql injection - using PreparedStatement

PreparedStatement is the best way to prevent sql injection in java, rather than escaping strings. 
Here's a simple example taking the user's input as the parameters:
public insertUser(String name, String email) {
   Connection conn = null;
   PreparedStatement stmt = null;
   try {
      conn = setupTheDatabaseConnectionSomehow();
      stmt = conn.prepareStatement("INSERT INTO person (name, email) values (?, ?)");
      stmt.setString(1, name);
      stmt.setString(2, email);
   finally {
      try {
         if (stmt != null) { stmt.close(); }
      catch (Exception e) {
         // log this error
      try {
         if (conn != null) { conn.close(); }
      catch (Exception e) {
         // log this error
No matter what characters are in name and email, those characters will be placed directly in the database. They won't affect the INSERT statement in any way.
There are different set methods for different data types -- which one you use depends on what your database fields are. For example, if you have an INTEGER column in the database, you should use asetInt method. The PreparedStatement documentation lists all the different methods available for setting and getting data.

redirect message to IO stream

How could Java classes direct program messages to the system console, but error messages, say to a file?
The class System has a variable out that represents the standard output, and the variable err that represents the standard error device. By default, they both point at the system console. This how the standard output could be re-directed:

Stream st = new Stream(new FileOutputStream("output.txt")); 

java socket connect read string

Java - create socket connection to HOST:PORT and read message from there
import java.util.*;

public class Time_Server_Socket_Test_Java {
    public static void main(String[] args) {
        try {
            Socket s = new Socket(HOST, PORT);//use your own HOST:PORT
            try {
                InputStream inStream = s.getInputStream();
                Scanner in = new Scanner(inStream);

                while (in.hasNextLine()) {
                    String line = in.nextLine();
            } finally {
        } catch (IOException e) {

How to serialize variables selectively

In a Java class, one has 10 variables. One wants to serialize only 3 variables,how can this be achieved?
->Make variables as 'transient' which are not to be serialized.

maximize a JFrame window in java

How to Maximize a JFrame :
    JFrame myFrame = new JFrame();
    myFrame.setExtendedState(myFrame.getExtendedState() | JFrame.MAXIMIZED_BOTH);

The usage of Java packages.

Explain the usage of Java packages.

A. This is a way to organize files when a project consists of multiple modules. It also helps resolve naming conflicts when different packages have classes with the same names. 
Packages access level also allows you to protect data from being used by the non-authorized classes.

Java: difference between private, protected, and public?

These keywords are for allowing privileges to components such as java methods and variables.
Public: accessible to all classes
Private: accessible only to the class to which they belong
Protected: accessible to the class to which they belong and any subclasses.

Access specifiers are keywords that determines the type of access to the member of a class. These are:
* Public
* Protected
* Private
* Defaults

java show window JFrame JDialog always on top

We have to use this feature of java.awt.Window : Window.alwaysOnTop(boolean); Example code :

import javax.swing.JFrame;
import javax.swing.JLabel;

public class Always_on_Top_JFrame_JAVA{
    public static void main(String[] args) {
        JFrame frame = new JFrame("Title - always on top :D ");
        // Set's the window to be "always on top"
        frame.setAlwaysOnTop( true );

        frame.setLocationByPlatform( true );
        frame.add( new JLabel(" Always on TOP ") );
        frame.setVisible( true );

Order of catching exception in java

Does it matter in what order catch statements for FileNotFoundException and IOExceptipon are written?

A. Yes, it does. The FileNotFoundException is inherited from the IOException. 
Exception's subclasses have to be caught first.

So while catching exceptions, we must catch the low level exception first - here : FileNotFoundException .

#The hierarchy in Java Exception framework :