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mysql> use kvs;
Database changed
mysql> show tables;
+---------------+
| Tables_in_kvs |
+---------------+
| dept |
| emp |
| emp1 |
| emp2 |
| emp3 |
| emp4 |
| emp5 |
| emp6 |
| emp7 |
| r1 |
| r2 |
| r3 |
| r4 |
| r5 |
| r6 |
| student |
| t1 |
| t2 |
| t3 |
| t4 |
| t5 |
| t6 |
| t7 |
| voters |
| voters1 |
| voters2 |
| voters3 |
+---------------+
27 rows in set (1.00 sec)
mysql> select * from emp;
+------+---------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+---------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
| 103 | Sam | 2010-10-10 | 38 | 95000.00 | Hindi |
| 104 | Priya | 2019-12-05 | 28 | 72000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 106 | Amit | 2020-12-05 | 28 | 72000.00 | Hindi |
| 107 | Pooja | 2021-12-10 | 28 | 65000.00 | Hindi |
| 108 | Riya | 2019-03-05 | 31 | 73000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 110 | Aman | 2019-02-05 | 31 | 72000.00 | CS |
| 109 | Rohan | NULL | 32 | NULL | Hindi |
| 111 | Shubham | 2021-10-10 | 25 | 65000.00 | Maths |
| 112 | Ajay | 2021-10-10 | 25 | 65000.00 | Maths |
+------+---------+------------+------+----------+---------+
12 rows in set (0.26 sec)
mysql> update emp set salary = 70000 where id=112;
Query OK, 1 row affected (0.58 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from emp;
+------+---------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+---------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
| 103 | Sam | 2010-10-10 | 38 | 95000.00 | Hindi |
| 104 | Priya | 2019-12-05 | 28 | 72000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 106 | Amit | 2020-12-05 | 28 | 72000.00 | Hindi |
| 107 | Pooja | 2021-12-10 | 28 | 65000.00 | Hindi |
| 108 | Riya | 2019-03-05 | 31 | 73000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 110 | Aman | 2019-02-05 | 31 | 72000.00 | CS |
| 109 | Rohan | NULL | 32 | NULL | Hindi |
| 111 | Shubham | 2021-10-10 | 25 | 65000.00 | Maths |
| 112 | Ajay | 2021-10-10 | 25 | 70000.00 | Maths |
+------+---------+------------+------+----------+---------+
12 rows in set (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.02 sec)
mysql> select * from emp;
+------+---------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+---------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
| 103 | Sam | 2010-10-10 | 38 | 95000.00 | Hindi |
| 104 | Priya | 2019-12-05 | 28 | 72000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 106 | Amit | 2020-12-05 | 28 | 72000.00 | Hindi |
| 107 | Pooja | 2021-12-10 | 28 | 65000.00 | Hindi |
| 108 | Riya | 2019-03-05 | 31 | 73000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 110 | Aman | 2019-02-05 | 31 | 72000.00 | CS |
| 109 | Rohan | NULL | 32 | NULL | Hindi |
| 111 | Shubham | 2021-10-10 | 25 | 65000.00 | Maths |
| 112 | Ajay | 2021-10-10 | 25 | 70000.00 | Maths |
+------+---------+------------+------+----------+---------+
12 rows in set (0.00 sec)
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> create table account(ac_no int,balance decimal);
Query OK, 0 rows affected (2.80 sec)
mysql> desc account;
+---------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+---------------+------+-----+---------+-------+
| ac_no | int | YES | | NULL | |
| balance | decimal(10,0) | YES | | NULL | |
+---------+---------------+------+-----+---------+-------+
2 rows in set (0.11 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> desc account;
+---------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+---------+---------------+------+-----+---------+-------+
| ac_no | int | YES | | NULL | |
| balance | decimal(10,0) | YES | | NULL | |
+---------+---------------+------+-----+---------+-------+
2 rows in set (0.01 sec)
mysql> show tables;
+---------------+
| Tables_in_kvs |
+---------------+
| account |
| dept |
| emp |
| emp1 |
| emp2 |
| emp3 |
| emp4 |
| emp5 |
| emp6 |
| emp7 |
| r1 |
| r2 |
| r3 |
| r4 |
| r5 |
| r6 |
| student |
| t1 |
| t2 |
| t3 |
| t4 |
| t5 |
| t6 |
| t7 |
| voters |
| voters1 |
| voters2 |
| voters3 |
+---------------+
28 rows in set (0.01 sec)
mysql> insert into account values(100,20000),(200,10000);
Query OK, 2 rows affected (0.15 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
+-------+---------+
2 rows in set (0.04 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> update account set balance=balance-100 where ac_no=100;
Query OK, 1 row affected (0.18 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> update account set balance=balance+100 where ac_no=200;
Query OK, 1 row affected (0.14 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 19900 |
| 200 | 10100 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 19900 |
| 200 | 10100 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> truncate account;
Query OK, 0 rows affected (1.56 sec)
mysql> commit;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
Empty set (0.20 sec)
mysql> set transaction;
ERROR 1064 (42000): 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 '' at line 1
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into account values(100,20000),(200,10000);
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> update account set balance=balance-100 where ac_no=100;
Query OK, 1 row affected (0.03 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> update account set balance=balance+100 where ac_no=200;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> rollback;
Query OK, 0 rows affected (0.09 sec)
mysql> select * from account;
Empty set (0.00 sec)
mysql> insert into account values(100,20000),(200,10000);
Query OK, 2 rows affected (0.16 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> update account set balance=balance-100 where ac_no=100;
Query OK, 1 row affected (0.08 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> update account set balance=balance+100 where ac_no=200;
Query OK, 1 row affected (0.15 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 19900 |
| 200 | 10100 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 19900 |
| 200 | 10100 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> trancate account;
ERROR 1064 (42000): 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 'trancate account' at line 1
mysql> truncate account;
Query OK, 0 rows affected (1.27 sec)
mysql> select * from account;
Empty set (0.24 sec)
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into account values(100,20000),(200,10000);
Query OK, 2 rows affected (0.03 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.06 sec)
mysql> select * from account;
Empty set (0.00 sec)
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into account values(100,20000),(200,10000);
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> update account set balance=balance-100 where ac_no=100;
Query OK, 1 row affected (0.04 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> update account set balance=balance+100 where ac_no=200;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 19900 |
| 200 | 10100 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.03 sec)
mysql> select * from account;
Empty set (0.01 sec)
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into account values(100,20000),(200,10000);
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> update account set balance=balance-100 where ac_no=100;
Query OK, 1 row affected (0.03 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> update account set balance=balance+100 where ac_no=200;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 19900 |
| 200 | 10100 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> commit;
Query OK, 0 rows affected (0.13 sec)
mysql> rollback;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 19900 |
| 200 | 10100 |
+-------+---------+
2 rows in set (0.00 sec)
mysql> truncate account;
Query OK, 0 rows affected (1.14 sec)
mysql> start transaction;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into account values(100,20000),(200,10000);
Query OK, 2 rows affected (0.14 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> insert into account values(300,25000);
Query OK, 1 row affected (0.00 sec)
mysql> savepoint A;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into account values(400,30000);
Query OK, 1 row affected (0.00 sec)
mysql> savepoint B;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into account values(500,40000);
Query OK, 1 row affected (0.00 sec)
mysql> savepoint C;
Query OK, 0 rows affected (0.00 sec)
mysql> insert into account values(600,50000);
Query OK, 1 row affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
| 300 | 25000 |
| 400 | 30000 |
| 500 | 40000 |
| 600 | 50000 |
+-------+---------+
6 rows in set (0.00 sec)
mysql> rollback to C;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
| 300 | 25000 |
| 400 | 30000 |
| 500 | 40000 |
+-------+---------+
5 rows in set (0.03 sec)
mysql> rollback to B;
Query OK, 0 rows affected (0.03 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
| 300 | 25000 |
| 400 | 30000 |
+-------+---------+
4 rows in set (0.00 sec)
mysql> rollback to A;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from account;
+-------+---------+
| ac_no | balance |
+-------+---------+
| 100 | 20000 |
| 200 | 10000 |
| 300 | 25000 |
+-------+---------+
3 rows in set (0.00 sec)
mysql> rollback;
Query OK, 0 rows affected (0.06 sec)
mysql> select * from account;
Empty set (0.00 sec)
mysql> show tables;
+---------------+
| Tables_in_kvs |
+---------------+
| account |
| dept |
| emp |
| emp1 |
| emp2 |
| emp3 |
| emp4 |
| emp5 |
| emp6 |
| emp7 |
| r1 |
| r2 |
| r3 |
| r4 |
| r5 |
| r6 |
| student |
| t1 |
| t2 |
| t3 |
| t4 |
| t5 |
| t6 |
| t7 |
| voters |
| voters1 |
| voters2 |
| voters3 |
+---------------+
28 rows in set (0.00 sec)
mysql> drop kvs;
ERROR 1064 (42000): 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 'kvs' at line 1
mysql> drop database kvs;
Query OK, 28 rows affected (7.90 sec)
mysql> show tables;
ERROR 1046 (3D000): No database selected
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| 12cs |
| abc |
| delhi |
| information_schema |
| leet |
| mysql |
| performance_schema |
| pysales_inventory |
| sakila |
| spsc |
| spsharmaclasses |
| spsharmag |
| sys |
| world |
+--------------------+
14 rows in set (0.06 sec)
mysql> create databases kvs;
ERROR 1064 (42000): 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 'databases kvs' at line 1
mysql> create database kvs;
Query OK, 1 row affected (0.09 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| 12cs |
| abc |
| delhi |
| information_schema |
| kvs |
| leet |
| mysql |
| performance_schema |
| pysales_inventory |
| sakila |
| spsc |
| spsharmaclasses |
| spsharmag |
| sys |
| world |
+--------------------+
15 rows in set (0.00 sec)
mysql> use kvs;
Database changed
mysql> show tables;
Empty set (0.02 sec)
mysql> show tables;
+---------------+
| Tables_in_kvs |
+---------------+
| account |
| dept |
| emp |
| emp1 |
| emp2 |
| emp3 |
| emp4 |
| emp5 |
| emp6 |
| emp7 |
| r1 |
| r2 |
| r3 |
| r4 |
| r5 |
| r6 |
| student |
| t1 |
| t2 |
| t3 |
| t4 |
| t5 |
| t6 |
| t7 |
| voters |
| voters1 |
| voters2 |
| voters3 |
+---------------+
28 rows in set (0.09 sec)
mysql> select * from emp;
+------+---------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+---------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
| 103 | Sam | 2010-10-10 | 38 | 95000.00 | Hindi |
| 104 | Priya | 2019-12-05 | 28 | 72000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 106 | Amit | 2020-12-05 | 28 | 72000.00 | Hindi |
| 107 | Pooja | 2021-12-10 | 28 | 65000.00 | Hindi |
| 108 | Riya | 2019-03-05 | 31 | 73000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 110 | Aman | 2019-02-05 | 31 | 72000.00 | CS |
| 109 | Rohan | NULL | 32 | NULL | Hindi |
| 111 | Shubham | 2021-10-10 | 25 | 65000.00 | Maths |
| 112 | Ajay | 2021-10-10 | 25 | 70000.00 | Maths |
+------+---------+------------+------+----------+---------+
12 rows in set (0.09 sec)
mysql> create table rohit as select * from emp;
Query OK, 12 rows affected, 1 warning (0.69 sec)
Records: 12 Duplicates: 0 Warnings: 1
mysql> select * from rohit;
+------+---------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+---------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
| 103 | Sam | 2010-10-10 | 38 | 95000.00 | Hindi |
| 104 | Priya | 2019-12-05 | 28 | 72000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 106 | Amit | 2020-12-05 | 28 | 72000.00 | Hindi |
| 107 | Pooja | 2021-12-10 | 28 | 65000.00 | Hindi |
| 108 | Riya | 2019-03-05 | 31 | 73000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 110 | Aman | 2019-02-05 | 31 | 72000.00 | CS |
| 109 | Rohan | NULL | 32 | NULL | Hindi |
| 111 | Shubham | 2021-10-10 | 25 | 65000.00 | Maths |
| 112 | Ajay | 2021-10-10 | 25 | 70000.00 | Maths |
+------+---------+------------+------+----------+---------+
12 rows in set (0.00 sec)
mysql> create table rohit1 as select * from emp where id<110;
Query OK, 9 rows affected, 1 warning (0.81 sec)
Records: 9 Duplicates: 0 Warnings: 1
mysql> select * from rohit1;
+------+-------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+-------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
| 103 | Sam | 2010-10-10 | 38 | 95000.00 | Hindi |
| 104 | Priya | 2019-12-05 | 28 | 72000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 106 | Amit | 2020-12-05 | 28 | 72000.00 | Hindi |
| 107 | Pooja | 2021-12-10 | 28 | 65000.00 | Hindi |
| 108 | Riya | 2019-03-05 | 31 | 73000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 109 | Rohan | NULL | 32 | NULL | Hindi |
+------+-------+------------+------+----------+---------+
9 rows in set (0.00 sec)
mysql> create table rohit2 as select id,name,salary from emp where id<110;
Query OK, 9 rows affected, 1 warning (0.50 sec)
Records: 9 Duplicates: 0 Warnings: 1
mysql> select * from rohit2;
+------+-------+----------+
| id | name | salary |
+------+-------+----------+
| 102 | Sita | 75000.00 |
| 103 | Sam | 95000.00 |
| 104 | Priya | 72000.00 |
| 105 | Raj | 80000.00 |
| 106 | Amit | 72000.00 |
| 107 | Pooja | 65000.00 |
| 108 | Riya | 73000.00 |
| 105 | Raj | 80000.00 |
| 109 | Rohan | NULL |
+------+-------+----------+
9 rows in set (0.00 sec)
mysql> create table rohit2(id int,age int);
ERROR 1050 (42S01): Table 'rohit2' already exists
mysql> create table if not exists rohit2(id int,age int);
Query OK, 0 rows affected, 1 warning (0.07 sec)
mysql> select * from rohit2;
+------+-------+----------+
| id | name | salary |
+------+-------+----------+
| 102 | Sita | 75000.00 |
| 103 | Sam | 95000.00 |
| 104 | Priya | 72000.00 |
| 105 | Raj | 80000.00 |
| 106 | Amit | 72000.00 |
| 107 | Pooja | 65000.00 |
| 108 | Riya | 73000.00 |
| 105 | Raj | 80000.00 |
| 109 | Rohan | NULL |
+------+-------+----------+
9 rows in set (0.00 sec)
mysql> select * from emp;
+------+---------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+---------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
| 103 | Sam | 2010-10-10 | 38 | 95000.00 | Hindi |
| 104 | Priya | 2019-12-05 | 28 | 72000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 106 | Amit | 2020-12-05 | 28 | 72000.00 | Hindi |
| 107 | Pooja | 2021-12-10 | 28 | 65000.00 | Hindi |
| 108 | Riya | 2019-03-05 | 31 | 73000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 110 | Aman | 2019-02-05 | 31 | 72000.00 | CS |
| 109 | Rohan | NULL | 32 | NULL | Hindi |
| 111 | Shubham | 2021-10-10 | 25 | 65000.00 | Maths |
| 112 | Ajay | 2021-10-10 | 25 | 70000.00 | Maths |
+------+---------+------------+------+----------+---------+
12 rows in set (0.03 sec)
mysql> select * from emp where exists (select salary where id=109);
+------+-------+------+------+--------+---------+
| id | name | DOJ | age | salary | subject |
+------+-------+------+------+--------+---------+
| 109 | Rohan | NULL | 32 | NULL | Hindi |
+------+-------+------+------+--------+---------+
1 row in set (0.04 sec)
mysql> select * from emp where exists (select salary where id=115);
Empty set (0.00 sec)
mysql> select * from emp where True;
+------+---------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+---------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
| 103 | Sam | 2010-10-10 | 38 | 95000.00 | Hindi |
| 104 | Priya | 2019-12-05 | 28 | 72000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 106 | Amit | 2020-12-05 | 28 | 72000.00 | Hindi |
| 107 | Pooja | 2021-12-10 | 28 | 65000.00 | Hindi |
| 108 | Riya | 2019-03-05 | 31 | 73000.00 | CS |
| 105 | Raj | 2018-01-23 | 33 | 80000.00 | CS |
| 110 | Aman | 2019-02-05 | 31 | 72000.00 | CS |
| 109 | Rohan | NULL | 32 | NULL | Hindi |
| 111 | Shubham | 2021-10-10 | 25 | 65000.00 | Maths |
| 112 | Ajay | 2021-10-10 | 25 | 70000.00 | Maths |
+------+---------+------------+------+----------+---------+
12 rows in set (0.00 sec)
mysql> select * from emp where False;
Empty set (0.00 sec)
mysql> select * from emp where id=120;
Empty set (0.00 sec)
mysql> select * from emp where id=102;
+------+------+------------+------+----------+---------+
| id | name | DOJ | age | salary | subject |
+------+------+------------+------+----------+---------+
| 102 | Sita | 2018-12-05 | 32 | 75000.00 | Hindi |
+------+------+------------+------+----------+---------+
1 row in set (0.00 sec)
mysql>
Microsoft Windows [Version 10.0.19042.1237]
(c) Microsoft Corporation. All rights reserved.
C:\WINDOWS\system32>cd C:\Program Files\MySQL\MySQL Server 8.0\bin
C:\Program Files\MySQL\MySQL Server 8.0\bin>mysqldump -uroot -proot kvs>kvsback.sql
mysqldump: [Warning] Using a password on the command line interface can be insecure.
C:\Program Files\MySQL\MySQL Server 8.0\bin>mysql -uroot -proot kvs<kvsback.sql
mysql: [Warning] Using a password on the command line interface can be insecure.
C:\Program Files\MySQL\MySQL Server 8.0\bin>
