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Let us first create a table −mysql> create table DemoTable ( Name varchar(40) ) ; Query OK, 0 rows affected (0.63 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John.Smith'); Query OK, 1 row affected (0.30 sec) mysql> insert into DemoTable values('Chris Brown'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('Chris.Brown'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values('David Miller'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values('Chris.Taylor'); Query OK, 1 row affected (0.18 sec)Display all records from the table using select ... Read More
Fir this, you can concatenate 0 with string field with the help of + operator. The scenario here is like we need to fetch numeric “9844” from a string field “9844Bob”.Let us first create a table −mysql> create table DemoTable ( StudentId varchar(100) ); Query OK, 0 rows affected (0.92 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('9844Bob'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('6375DavidMiller'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('007'); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable ... Read More
Let us first create a table −mysql> create table DemoTable ( Value float ); Query OK, 0 rows affected (0.95 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(12.4567); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values(124.7884); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values(45.64643); Query OK, 1 row affected (0.46 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+---------+ | Value | +---------+ | 12.4567 | | 124.788 | | 45.6464 | +---------+ ... Read More
For this, the syntax is as follows −DELIMITER // create trigger yourTriggerName before insert on yourTableName1 for each row begin insert into yourTableName2 values (yourValue1, yourValue2, ...N); end ; // DELIMITER ;Let us first create a table −mysql> create table DemoTable1 ( StudentId int, StudentName varchar(40) ); Query OK, 0 rows affected (0.69 sec)Here is the query to create second table −mysql> create table DemoTable2( Id int, Name varchar(40) ); Query OK, 0 rows affected (0.61 sec)Here is the query for trigger before insert −mysql> DELIMITER // mysql> create trigger ... Read More
Let’s say the current date is 2019-09-14 8 :50 :10. Now, we want records from 00 :00 to 2019-09-14 8 :50 :10. Let us now see an example and create a table −mysql> create table DemoTable ( DueDate datetime ); Query OK, 0 rows affected (0.66 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('2019-09-14'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values('2019-09-14 8 :00 :10'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('2019-09-14 8 :44 :00'); Query OK, 1 row affected (0.14 sec) mysql> insert ... Read More
To exclude records, use MySQL NOT IN(). Let us first create a table −mysql> create table DemoTable ( Id int ); Query OK, 0 rows affected (0.64 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(1); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values(2); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(3); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable values(4); Query OK, 1 row affected (0.41 sec) mysql> insert into DemoTable values(5); Query OK, 1 row affected (0.09 sec) mysql> insert into ... Read More
Let us first create a table −mysql> create table DemoTable ( Name varchar(40), Position int ); Query OK, 0 rows affected (1.17 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris', 90); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('David', 67); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values('Bob', 55); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('Sam', 40); Query OK, 1 row affected (0.15 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the ... Read More
For this, use aggregate function COUNT() and GROUP BY to group those specific records for occurrences. Let us first create a table −mysql> create table DemoTable ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentSubject varchar(40) ); Query OK, 0 rows affected (5.03 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(StudentSubject) values('MySQL'); Query OK, 1 row affected (0.78 sec) mysql> insert into DemoTable(StudentSubject) values('Java'); Query OK, 1 row affected (0.39 sec) mysql> insert into DemoTable(StudentSubject) values('MySQL'); Query OK, 1 row affected (1.12 sec) mysql> insert into DemoTable(StudentSubject) values('MongoDB'); Query OK, 1 row affected ... Read More
To find a match from records, use MySQL IN(). Let us first create a table −mysql> create table DemoTable ( Id int, FirstName varchar(20), Gender ENUM('Male', 'Female') ); Query OK, 0 rows affected (1.73 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(1, 'Chris', 'Male'); Query OK, 1 row affected (0.47 sec) mysql> insert into DemoTable values(10, 'Emma', 'Female'); Query OK, 1 row affected (1.88 sec) mysql> insert into DemoTable values(9, 'Emma', 'Male'); Query OK, 1 row affected (0.70 sec) mysql> insert into DemoTable values(11, 'Isabella', 'Female'); Query OK, 1 row affected ... Read More
For this, use REGEXP. For example, characters J, A, V and A. Let us first create a table −mysql> create table DemoTable ( Value varchar(50) ); Query OK, 0 rows affected (3.92 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('XYSJGHAKLMVDFFSA'); Query OK, 1 row affected (0.67 sec) mysql> insert into DemoTable values('PQRSTJAVAL'); Query OK, 1 row affected (0.58 sec) mysql> insert into DemoTable values('SJATUVAK'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('JSTUVA'); Query OK, 1 row affected (0.32 sec)Display all records from the table using select statement −mysql> select ... Read More