Error executing MySQL query from an Arduino - mysql

Question

I'm using the following code:
void setup() {
mySerial = new Serial( this, "COM8", 115200 );
output = createWriter( "data.txt" );
msql = new MySQL( this, "localhost", "arduino", "root","" );
if ( msql.connect() )
{output.println("connected");}
else{output.println("not connected");}
// output = open( "data.txt" );
}
void draw() {
if (mySerial.available() > 0 ) {
int d = day();
int m = month();
int y = year();
int s = second(); // Values from 0 - 59
int min = minute(); // Values from 0 - 59
int h = hour();
String a = String.valueOf(d);
String b = String.valueOf(m);
String c = String.valueOf(y);
String value = mySerial.readString();
if ( value != null ) {
output.print( value );
String state=value;
String x=a+"/"+b+"/"+c;
String z=h+":"+min+":"+s;
output.println(x);
output.println(z);
msql.execute( "INSERT INTO info(status,date,time) VALUES ("+state+","+x+","+z+");" );
}
}
But receive this error:
Error: Using driver com.mysql.jdbc.Driver 3.1 SQL.query():
java.sql.SQLException.
INSERT INTO info(status,date,time) VALUES (No detect
,20/3/2015,20:7:23); java.sql.SQLException: You have an error in your
SQL syntax; check the manual that corresponds to your MySQL server
version for the right syntax to use near 'detect ,20/3/2015,20:7:23)'
at line 1
How can this be resolved?