Database Articles - Page 299 of 671

To convert MySQL timestamp to UNIX Timestamp, use the UNIX_TIMESTAMP(). Following is the syntax −select unix_timestamp(yourColumnName) from yourTableName;Let us first create a table −mysql> create table DemoTable(    Duetimestamp timestamp ); Query OK, 0 rows affected (2.66 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(now()); Query OK, 1 row affected (1.53 sec) mysql> insert into DemoTable values('2016-01-21 12:34:00'); Query OK, 1 row affected (0.73 sec) mysql> insert into DemoTable values('2018-05-01 02:00:00'); Query OK, 1 row affected (0.42 sec) mysql> insert into DemoTable values('2017-03-02 01:10:20'); Query OK, 1 row affected (10.19 sec)Display all records from ... Read More

To replace & with an ampersand, use MySQL REPLACE(). Let us first create a table −mysql> create table DemoTable(    Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    Value varchar(100) ); Query OK, 0 rows affected (1.06 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(Value) values('@amp'); Query OK, 1 row affected (0.33 sec) mysql> insert into DemoTable(Value) values('&'); Query OK, 1 row affected (1.09 sec) mysql> insert into DemoTable(Value) values('#amp'); Query OK, 1 row affected (0.28 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+----+-------+ ... Read More

Let us first create a table −mysql> create table DemoTable(    Value int,    Value2 varchar(100) ); Query OK, 0 rows affected (0.84 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(10, '999.999.999.999'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values(20, '888.888.888.888'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(30, '999.999.999.999'); Query OK, 1 row affected (0.09 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+-------+-----------------+ | Value | Value2 ... Read More

Yes, we can do that. Let us first create a table −mysql> create table DemoTable(    Id int ); Query OK, 0 rows affected (1.02 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(201); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable values(202); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable values(290); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(301); Query OK, 1 row affected (0.13 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+------+ ... Read More

The @@identity returns the last inserted value in the auto_increment column in the current session. Let us first create a table −mysql> create table DemoTable(    UserId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    UserName varchar(100) ); Query OK, 0 rows affected (0.67 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(UserName) values('David'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable(UserName) values('Mike'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable(UserName) values('Carol'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable(UserName) values('Robert'); Query OK, 1 row affected (0.24 sec) ... Read More

Let us first create a table −mysql> create table DemoTable(    ProductName varchar(100),    ProductPrice int ); Query OK, 0 rows affected (0.68 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Product-1', 56); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('Product-2', 78); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values('Product-1', 88); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('Product-2', 86); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Product-1', 45); Query OK, 1 row affected (0.18 sec) mysql> insert into ... Read More

If you will extend the size of a varchar field in MySQL then it won’t affect the data inside it.Let us first create a table −mysql> create table DemoTable(    Name varchar(8) ); Query OK, 0 rows affected (1.11 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Robert'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('Mike'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('Sam'); Query OK, 1 row affected (0.13 sec)Display all records from the ... Read More

Let us first create a table −mysql> create table DemoTable(    FirstName varchar(100) ); Query OK, 0 rows affected (0.97 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris'); Query OK, 1 row affected (0.31 sec) mysql> insert into DemoTable values('Adam'); Query OK, 1 row affected (0.35 sec) mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable values('Sam'); Query OK, 1 row affected (0.37 sec) mysql> insert into DemoTable values('Mike'); Query OK, 1 row affected (0.27 sec) mysql> insert into DemoTable values('David'); Query OK, 1 row affected (0.27 ... Read More

For this, you can use a PREPARE statement. Let us first create a table −mysql> create table DemoTable(    FirstName varchar(100),    CountryName varchar(100) ); Query OK, 0 rows affected (0.53 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Adam', 'US'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('Chris', 'AUS'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('Robert', 'UK'); Query OK, 1 row affected (0.32 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+-----------+-------------+ | FirstName | ... Read More

For this, use the GROUP BY HAVING clause. Let us first create a table −mysql> create table DemoTable(    Name varchar(100),    Age int ); Query OK, 0 rows affected (1.50 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris', 23); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('David', 21); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('Chris', 23); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Chris', 21); Query OK, 1 row affected (0.27 sec) mysql> insert into DemoTable values('Mike', 25); Query OK, ... Read More