13, అక్టోబర్ 2013, ఆదివారం

Celkon CT910+ HD tablet with voice calling launched for Rs. 7,999


Celkon-tablet-HD.jpg

Celkon Mobiles has launched yet another tablet in the Indian market - CT910+ HD. Celkon CT910+ comes with a 7-inch five point touch display.The screen resolution of this tablet is 960x540 pixels. Celkon CT910+ packs in a 1GHz dual-core processor with 512MB of RAM. The tablet has an internal storage of 4GB, of which 1.7GB is user accessible.
For camera, there is a 2-megapixel rear camera and a VGA front camera. Celkon CT910+ comes with 3500mAh battery and runs on Android 4.1 (Jelly Bean). It is a 3G tablet that supports voice calling. Other connectivity options include Wi-Fi, Bluetooth and GPS. The tablet comes with a price tag of Rs. 7,999.
This tablet will be competing with the likes of Micromax Funbook Talk P362 Tablet, Lava E-Tab XTRON+ and Zync Dual 7.0. All these are 7-inch offerings. Micromax Funbook Talk P362 comes with a screen resolution of 480X800 pixels. It is powered by 1.2GHz dual-core Cortex A9 processor with 1GB of RAM. The tablet has a 4GB internal storage that can be expanded by up to 32GB via microSD card. This tablet runs on Android 4.1 (Jelly Bean) and is available at a best buy price of Rs. 6,999
Priced at Rs. 6,990, Lava E-Tab XTRON+ comes with 7-inch capacitive multi-touch IPS display and has a resolution of 1024X600 pixels. It is powered by a 1.5GHz dual-core processor along with 1GB of RAM and 8GB of internal storage, which can be further expanded by up to 32GB via a microSD card. This tablet runs on Android 4.2.2 (Jelly Bean), and has a 3,700mAh battery.
Zync Dual 7.0 is priced at Rs. 5,990 and has a screen resolution of 800X480 pixels. It comes with 1.6 GHz dual-core tablet with 1GB of RAM, 8GB of internal storage. There is a 0.3-megapixel front camera and a 2-megapixel rear camera. The tablet runs on Android 4.1 (Jelly Bean) and is powered by 3,000mAh battery.
Celkon CT910+ HD key specifications
  • 7-inch display
  • 1GHz dual-core processor
  • 512MB RAM
  • 4GB Internal storage
  • 2-megapixel rear camera
  • VGA front camera
  • 3G with Voice Calling, Wi-Fi, Bluetooth and GPS
  • 3500mAh battery
  • Android 4.1.2 Jelly bean
For the latest technology news and reviews, like us on Facebook or follow us on Twitter and get the NDTV Gadgets app for Android or iOS.

ABOUT THE INTEGERITY CONSTARAINTS IN ORACLE



SQL> select seq1.nextval from dual;

   NEXTVAL
----------
        25

SQL> select seq1.currval from dual;

   CURRVAL
----------
        25

SQL> create sequence seq2 minvalue 1 maxvalue 1000 start with 1 increment by -2
cache 5;

Sequence created.

SQL> select seq1.currval from dual;

   CURRVAL
----------
        25

SQL> select seq2.currval from dual;
select seq2.currval from dual
       *
ERROR at line 1:
ORA-08002: sequence SEQ2.CURRVAL is not yet defined in this session


SQL> select seq2.nextval from dual;

   NEXTVAL
----------
         1

SQL> select seq2.nextval from dual;
select seq2.nextval from dual
                         *
ERROR at line 1:
ORA-08004: sequence SEQ2.NEXTVAL goes below MINVALUE and cannot be instantiated


SQL> select seq2.currval from dual;

   CURRVAL
----------
         1

SQL> select * from dept;

    DEPTNO DNAME                     NOEMP
---------- -------------------- ----------
         1 production                   22
         2 marketing                    30
         3 finance                      15
         4 auditing                     20
         5 hr                           10
         6 management                   25

6 rows selected.

SQL> create synonym ramusyn for dept;

Synonym created.

SQL> select * from ramusyn;

    DEPTNO DNAME                     NOEMP
---------- -------------------- ----------
         1 production                   22
         2 marketing                    30
         3 finance                      15
         4 auditing                     20
         5 hr                           10
         6 management                   25

6 rows selected.

SQL> select * from ramusyn;

    DEPTNO DNAME                     NOEMP
---------- -------------------- ----------
         1 production                   22
         2 marketing                    30
         3 finance                      15
         4 auditing                     20
         5 hr                           10
         6 management                   25

6 rows selected.

SQL> create table un(accno number(3) unique, not null);
create table un(accno number(3) unique, not null)
                                        *
ERROR at line 1:
ORA-00904: : invalid identifier


SQL> create table un(accno number(3) unique);

Table created.

SQL> create table un1(accno number(3) not null);

Table created.

SQL> insert into un1 values(&accno);
Enter value for accno: 100
old   1: insert into un1 values(&accno)
new   1: insert into un1 values(100)

1 row created.

SQL> /
Enter value for accno: 100
old   1: insert into un1 values(&accno)
new   1: insert into un1 values(100)

1 row created.

SQL> select * from un1;

     ACCNO
----------
       100
       100

SQL> /

     ACCNO
----------
       100
       100

SQL> insert into un1 values(&accno);
Enter value for accno:
old   1: insert into un1 values(&accno)
new   1: insert into un1 values()
insert into un1 values()
                       *
ERROR at line 1:
ORA-00936: missing expression


SQL> insert into un values(&accno);
Enter value for accno: 100
old   1: insert into un values(&accno)
new   1: insert into un values(100)

1 row created.

SQL> /
Enter value for accno: 100
old   1: insert into un values(&accno)
new   1: insert into un values(100)
insert into un values(100)
*
ERROR at line 1:
ORA-00001: unique constraint (SYSTEM.SYS_C004030) violated


SQL> /
Enter value for accno:
old   1: insert into un values(&accno)
new   1: insert into un values()
insert into un values()
                      *
ERROR at line 1:
ORA-00936: missing expression


SQL> /
Enter value for accno: null
old   1: insert into un values(&accno)
new   1: insert into un values(null)

1 row created.

SQL> select *from un;

     ACCNO
----------
       100


SQL>                 *
ERROR at line 1:
ORA-00907: missing right parenthesis


SQL> create table tra(accno number , trans varchar2(1), amount number(3), constr
aint noway forigen key(accno) references master(accno));
create table tra(accno number , trans varchar2(1), amount number(3), constraint
noway forigen key(accno) references master(accno))

                 *
ERROR at line 1:
ORA-00907: missing right parenthesis



























A live demonstration for the primary key, foreign keys and not null keys
SQL> CREATE TABLE CUSTOMERS(
  2         ID   INT              NOT NULL,
  3         NAME VARCHAR (20)     NOT NULL,
  4         AGE  INT              NOT NULL,
  5         ADDRESS  CHAR (25) ,
  6         SALARY   DECIMAL (18, 2),
  7         PRIMARY KEY (ID)
  8  );

Table created.
SQL> CREATE TABLE ORDERS (
  2         ID          INT        NOT NULL,
  3         DATE        DATETIME,  //here the problem is  coming
  4         CUSTOMER_ID INT references CUSTOMERS(ID),
  5         AMOUNT     double,
  6         PRIMARY KEY (ID)
  7  );
       DATE        DATETIME,  ERROR at line 3:  ORA-00904: : invalid identifier

SQL> create table orders(id int not null, c_id int references customers(id), pri
mary key(id));
Table created.
SQL> desc customers;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 ID                                        NOT NULL NUMBER(38)
 NAME                                      NOT NULL VARCHAR2(20)
 AGE                                       NOT NULL NUMBER(38)
 ADDRESS                                            CHAR(25)
 SALARY                                             NUMBER(18,2)

SQL> desc orders;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 ID                                        NOT NULL NUMBER(38)
 C_ID                                               NUMBER(38)

SQL> insert into customers values(&id , '&name' , &age , '&address' , &salary);
Enter value for id: 10
Enter value for name: ramu
Enter value for age: 36
Enter value for address: jimma
Enter value for salary: 1000
old   1: insert into customers values(&id , '&name' , &age , '&address' , &salary)
new   1: insert into customers values(10 , 'ramu' , 36 , 'jimma' , 1000)
1 row created.

SQL> insert into orders values(12345, 11);
insert into orders values(12345, 11)
*ERROR at line 1: ORA-02291: integrity constraint (SYSTEM.SYS_C004040) violated - parent key not found

SQL> insert into orders values(12345, 10);
1 row created.

sql fundamentals





SQL> select *from persons;
no rows selected

SQL> insert into person values('ramu',35);          1 row created.
SQL> insert into person values('ravi',35);             1 row created.

SQL> select *from person;

NAME                        AGE
-------------------- ----------
ramu                         35
ravi                         35

SQL> commit;          Commit complete.

SQL> savepoint ramu;   Savepoint created.

SQL> insert into person values('rajesh',65);
1 row created.

SQL> select * from person;
NAME                        AGE
-------------------- ----------
ramu                         35
ravi                         35
rajesh                       65


SQL> rollback to ramu;
Rollback complete.



SQL> select *from person;
NAME                        AGE
-------------------- ----------
ramu                         35
ravi                         35

SQL> select *from persons;
no rows selected

SQL> desc persons;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 PNAME                                              VARCHAR2(20)
 PAGE                                      NOT NULL NUMBER(3)

SQL> drop table persons;
Table dropped.

SQL> select * from person;

NAME                        AGE
-------------------- ----------
ramu                         35
ravi                         35



SQL> alter table person modify age number(4);
Table altered.

SQL> desc person;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 NAME                                               VARCHAR2(20)
 AGE                                       NOT NULL NUMBER(4)

alter command comes with 4 options
  2  alter-modify
  3  alter-add
  4  alter-rename
  5  alter-drop;


SQL> alter table person rename age to xage;
alter table person rename age to xage
                          *
ERROR at line 1:
ORA-14155: missing PARTITION or SUBPARTITION keyword


SQL> alter table person rename to persons;                 Table altered.
SQL> alter table persons add(mobile number(10));
Table altered.
SQL> desc persons;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 NAME                                               VARCHAR2(20)
 AGE                                       NOT NULL NUMBER(4)
 MOBILE                                             NUMBER(10)



SQL> alter table persons drop column mobile;

Table altered.

SQL> desc persons;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 NAME                                               VARCHAR2(20)
 AGE                                       NOT NULL NUMBER(4)

SQL> flashback table persons to before drop;
flashback table persons to before drop
*
ERROR at line 1:
ORA-38305: object not in RECYCLE BIN


SQL> drop table persons;

Table dropped.



SQL> purge table persons;
purge table persons
*
ERROR at line 1:
ORA-38307: object not in RECYCLE BIN


SQL> select seq1.nextval from dual;

   NEXTVAL
----------
        25

SQL> select seq1.currval from dual;

   CURRVAL
----------
        25

SQL> create sequence seq2 minvalue 1 maxvalue 1000 start with 1 increment by -2
cache 5;

Sequence created.

SQL> select seq1.currval from dual;

   CURRVAL
----------
        25

SQL> select seq2.currval from dual;
select seq2.currval from dual
       *
ERROR at line 1:
ORA-08002: sequence SEQ2.CURRVAL is not yet defined in this session


SQL> select seq2.nextval from dual;

   NEXTVAL
----------
         1

SQL> select seq2.nextval from dual;
select seq2.nextval from dual
                         *
ERROR at line 1:
ORA-08004: sequence SEQ2.NEXTVAL goes below MINVALUE and cannot be instantiated


SQL> select seq2.currval from dual;

   CURRVAL
----------
         1

SQL> select * from dept;

    DEPTNO DNAME                     NOEMP
---------- -------------------- ----------
         1 production                   22
         2 marketing                    30
         3 finance                      15
         4 auditing                     20
         5 hr                           10
         6 management                   25

6 rows selected.

SQL> create synonym ramusyn for dept;

Synonym created.

SQL> select * from ramusyn;

    DEPTNO DNAME                     NOEMP
---------- -------------------- ----------
         1 production                   22
         2 marketing                    30
         3 finance                      15
         4 auditing                     20
         5 hr                           10
         6 management                   25

6 rows selected.

SQL> select * from ramusyn;

    DEPTNO DNAME                     NOEMP
---------- -------------------- ----------
         1 production                   22
         2 marketing                    30
         3 finance                      15
         4 auditing                     20
         5 hr                           10
         6 management                   25

6 rows selected.

SQL> create table un(accno number(3) unique, not null);
create table un(accno number(3) unique, not null)
                                        *
ERROR at line 1:
ORA-00904: : invalid identifier


SQL> create table un(accno number(3) unique);

Table created.

SQL> create table un1(accno number(3) not null);

Table created.

SQL> insert into un1 values(&accno);
Enter value for accno: 100
old   1: insert into un1 values(&accno)
new   1: insert into un1 values(100)

1 row created.

SQL> /
Enter value for accno: 100
old   1: insert into un1 values(&accno)
new   1: insert into un1 values(100)

1 row created.

SQL> select * from un1;

     ACCNO
----------
       100
       100

SQL> /

     ACCNO
----------
       100
       100

SQL> insert into un1 values(&accno);
Enter value for accno:
old   1: insert into un1 values(&accno)
new   1: insert into un1 values()
insert into un1 values()
                       *
ERROR at line 1:
ORA-00936: missing expression


SQL> insert into un values(&accno);
Enter value for accno: 100
old   1: insert into un values(&accno)
new   1: insert into un values(100)

1 row created.

SQL> /
Enter value for accno: 100
old   1: insert into un values(&accno)
new   1: insert into un values(100)
insert into un values(100)
*
ERROR at line 1:
ORA-00001: unique constraint (SYSTEM.SYS_C004030) violated


SQL> /
Enter value for accno:
old   1: insert into un values(&accno)
new   1: insert into un values()
insert into un values()
                      *
ERROR at line 1:
ORA-00936: missing expression


SQL> /
Enter value for accno: null
old   1: insert into un values(&accno)
new   1: insert into un values(null)

1 row created.

SQL> select *from un;

     ACCNO
----------
       100

SQL> ed
SP2-0110: Cannot create save file "afiedt.buf"
SQL> select *from master;

no rows selected

SQL> desc master;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 ACCNO                                     NOT NULL NUMBER
 NAME                                               VARCHAR2(20)
 ADDRESS                                            VARCHAR2(20)
 AMOUNT                                             NUMBER

SQL> create table transc(accno number references master (accno),  trans varchar2
(1), amount number);

Table created.
SQL>                 *
ERROR at line 1:
ORA-00907: missing right parenthesis

A live demonstration for the primary key, foreign keys and not null keys
SQL> CREATE TABLE CUSTOMERS(
  2         ID   INT              NOT NULL,
  3         NAME VARCHAR (20)     NOT NULL,
  4         AGE  INT              NOT NULL,
  5         ADDRESS  CHAR (25) ,
  6         SALARY   DECIMAL (18, 2),
  7         PRIMARY KEY (ID)
  8  );

Table created.
SQL> CREATE TABLE ORDERS (
  2         ID          INT        NOT NULL,
  3         DATE        DATETIME,  //here the problem is  coming
  4         CUSTOMER_ID INT references CUSTOMERS(ID),
  5         AMOUNT     double,
  6         PRIMARY KEY (ID)
  7  );
       DATE        DATETIME,  ERROR at line 3:  ORA-00904: : invalid identifier

SQL> create table orders(id int not null, c_id int references customers(id), pri
mary key(id));
Table created.
SQL> desc customers;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 ID                                        NOT NULL NUMBER(38)
 NAME                                      NOT NULL VARCHAR2(20)
 AGE                                       NOT NULL NUMBER(38)
 ADDRESS                                            CHAR(25)
 SALARY                                             NUMBER(18,2)

SQL> desc orders;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------

 ID                                        NOT NULL NUMBER(38)
 C_ID                                               NUMBER(38)

SQL> insert into customers values(&id , '&name' , &age , '&address' , &salary);
Enter value for id: 10
Enter value for name: ramu
Enter value for age: 36
Enter value for address: jimma
Enter value for salary: 1000
old   1: insert into customers values(&id , '&name' , &age , '&address' , &salary)
new   1: insert into customers values(10 , 'ramu' , 36 , 'jimma' , 1000)
1 row created.

SQL> insert into orders values(12345, 11);
insert into orders values(12345, 11)
*ERROR at line 1: ORA-02291: integrity constraint (SYSTEM.SYS_C004040) violated - parent key not found

SQL> insert into orders values(12345, 10);
1 row created.