Found 4378 Articles for MySQL

Convert from varchar to datetime and compare in MySQL?

AmitDiwan
Updated on 12-Dec-2019 06:56:00

1K+ Views

For this, you can use STR_TO_DATE(). Let us first create a table −mysql> create table DemoTable1565    -> (    -> ArrivalDatetime varchar(40)    -> ); Query OK, 0 rows affected (0.82 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1565 values('10/01/2019 21:29:35'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable1565 values('10/13/2019 4:56:00'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable1565 values('10/13/2018 12:40:46'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable1565 values('10/13/2019 21:30:00'); Query OK, 1 row affected (0.58 sec)Display all records from the table using select ... Read More

CASE WHEN column1 IS NULL THEN NULL ELSE column2 END with MySQL

AmitDiwan
Updated on 12-Dec-2019 06:55:06

2K+ Views

For this, you can use the CASE statement. Let us first create a table−mysql> create table DemoTable    -> (    -> Name varchar(20),    -> Marks1 int,    -> Marks2 int    -> ); Query OK, 0 rows affected (0.72 sec)Insert some records in the table using insert command−mysql> insert into DemoTable values('Chris', 45, null); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('David', null, 78); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Bob', 67, 98); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> ... Read More

How to make MySQL result set the same as specified?

AmitDiwan
Updated on 12-Dec-2019 06:52:37

72 Views

For this, use MySQL FIND_IN_SET(). Let us first create a table −mysql> create table DemoTable1563    -> (    -> StudentId int,    -> StudentName varchar(20)    -> ); Query OK, 0 rows affected (0.52 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1563 values(1001, 'Chris'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable1563 values(1010, 'Bob'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable1563 values(1005, 'Chris'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable1563 values(1015, 'David'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable1563 ... Read More

Sorting max to min value in MySQL

AmitDiwan
Updated on 12-Dec-2019 06:51:34

663 Views

To sort from max to min value, use ORDER BY length(). Let us first create a table −mysql> create table DemoTable    -> (    -> Price varchar(20)    -> ); Query OK, 0 rows affected (0.92 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('80'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values('800'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('108'); Query OK, 1 row affected (0.50 sec) mysql> insert into DemoTable values('765'); Query OK, 1 row affected (0.14 sec)Display all records from the table using ... Read More

Should I name the username field in my MySQL table “name” or “user_name”?

AmitDiwan
Updated on 12-Dec-2019 06:50:43

250 Views

Do not prefix table name with field name like user_name. Instead, use user or username.If you prefix table name, then there may be a chance of ambiguity, so avoid prefixing table name.Let us first create a table −mysql> create table user    -> (    -> username varchar(20),    -> password varchar(20)    -> ); Query OK, 0 rows affected (0.66 sec)Insert some records in the table using insert command −mysql> insert into user values('John', 'J_635'); Query OK, 1 row affected (0.34 sec) mysql> insert into user values('Carol', 'Carol2212'); Query OK, 1 row affected (0.16 sec) mysql> insert into user ... Read More

Counting voucher value total since the beginning of the month and year in MySQL

AmitDiwan
Updated on 12-Dec-2019 06:49:05

78 Views

For this, use MySQL MONTH() and YEAR() methods. Let us first create a table −mysql> create table DemoTable1562    -> (    -> VoucherValue int,    -> RechargeDate date    -> ); Query OK, 0 rows affected (1.40 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1562 values(149, '2019-10-21'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable1562 values(199, '2019-10-13'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable1562 values(399, '2018-10-13'); Query OK, 1 row affected (0.25 sec) mysql> insert into DemoTable1562 values(450, '2019-10-13'); Query OK, 1 row affected (0.20 sec)Display all ... Read More

MySQL query to fetch multiple least values?

AmitDiwan
Updated on 12-Dec-2019 06:48:21

122 Views

For this, you can use a sub query along with MIN(). Let us first create a table−mysql> create table DemoTable    -> (    -> Name varchar(20),    -> Score int    -> ); Query OK, 0 rows affected (0.56 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John', 56); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('John', 45); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable values('John', 58); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Chris', 43); Query OK, 1 row affected (0.15 ... Read More

What's the most efficient way to pull data from MySQL so that it is formatted with duplicate values

AmitDiwan
Updated on 12-Dec-2019 06:46:56

77 Views

For this, you can use GROUP_CONCAT(). Let us first create a table −mysql> create table DemoTable1561    -> (    -> StudentName varchar(20),    -> Title text    -> ); Query OK, 0 rows affected (0.60 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1561 values('Adam', 'Learning Java'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable1561 values('Bob', 'Learning C'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable1561 values('Adam', 'Learning Spring and Hibernate Framework'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable1561 values('Carol', 'Learning MySQL from basic'); Query ... Read More

Using ! operator in MySQL

AmitDiwan
Updated on 12-Dec-2019 06:45:17

67 Views

For same results, do not use ! operator. The NOT keyword is already provided by MySQL. Let us first create a table −mysql> create table DemoTable1560    -> (    -> Value1 int    -> ); Query OK, 0 rows affected (0.50 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1560 values(0); Query OK, 1 row affected (0.16 sec)Display all records from the table using select statement −mysql> select * from DemoTable1560;This will produce the following output −+--------+ | Value1 | +--------+ |      0 | +--------+ 1 row in set (0.00 sec)Here is the ... Read More

Fix Error in MySQL syntax while creating a table column with name “index”?

AmitDiwan
Updated on 12-Dec-2019 06:46:06

683 Views

You can’t use the index as a column name because it is a reserved word. For this, you need to use backticks around the column name.If you will use a reserved word as the column name, you can see the following error−mysql> create table DemoTable    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> index int    -> )ENGINE=MyISAM; 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 'int )ENGINE=MyISAM' at line 4Let us first ... Read More

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