Found 4219 Articles for MySQLi

How to detect if a MySQL database structure changed (not content)?

AmitDiwan
Updated on 06-Jul-2020 11:39:59

211 Views

Let us first see an example and create a table −mysql> create table DemoTable (    StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    StudentName varchar(40),    StudentAge int,    StudentMarks int ); Query OK, 0 rows affected (0.76 sec)Following is the query to know the database structure −mysql> show create table DemoTable;This will produce the following output −+---------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table         | Create Table                                                                 ... Read More

Exclude some ID records from a list and display rest in MySQL

AmitDiwan
Updated on 09-Oct-2019 12:22:59

651 Views

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

A single MySQL query to update only specific records in a range without updating the entire column

AmitDiwan
Updated on 09-Oct-2019 12:20:01

129 Views

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

Count the occurrences of specific records (duplicate) in one MySQL query

AmitDiwan
Updated on 09-Oct-2019 12:16:21

91 Views

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

MySQL query to find a match and fetch records

AmitDiwan
Updated on 09-Oct-2019 12:13:18

340 Views

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

Search for specific characters within a string with MySQL?

AmitDiwan
Updated on 09-Oct-2019 12:10:10

315 Views

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

Count values greater and less than a specific number and display count in separate MySQL columns?

AmitDiwan
Updated on 09-Oct-2019 12:07:56

915 Views

For this, you can use COUNT() along with CASE STATEMENT. Let us first create a table −mysql> create table DemoTable (    Score int ); Query OK, 0 rows affected (0.71 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(40); Query OK, 1 row affected (0.77 sec) mysql> insert into DemoTable values(48); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values(59); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values(33); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values(38); Query OK, 1 row affected (0.09 sec) ... Read More

How to select a specific record from MySQL if date is in VARCHAR format?

AmitDiwan
Updated on 09-Oct-2019 12:06:06

159 Views

For this, use STR_TO_DATE(). Let us first create a table −mysql> create table DemoTable (    DueDate varchar(60) ) ; Query OK, 0 rows affected (0.71 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('12-AUG-2016'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('14-AUG-2018'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('24-AUG-2012'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('14-AUG-2012'); Query OK, 1 row affected (0.19 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output ... Read More

Use MySQL to find duplicates and display in a single line

AmitDiwan
Updated on 09-Oct-2019 12:04:05

220 Views

For this, you can use GROUP_CONCAT() along with GROUP BY clause. Both are used to group concat duplicates and display in a single line. Let us first create a table −mysql> create table DemoTable (    StudentFavouriteSubject varchar(40),    StudentName varchar(40) ) ; Query OK, 0 rows affected (0.75 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('MySQL', 'Chris'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable values('MongoDB', 'Bob'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('MySQL', 'Sam'); Query OK, 1 row affected (0.10 sec) mysql> insert into ... Read More

Can I search for particular numbers in a MySQL column with comma separated records using a MySQL query?

AmitDiwan
Updated on 09-Oct-2019 11:59:14

222 Views

Yes, you can search for particular numbers using the MySQL FIND_IN_SET(). Let us first create a table −mysql> create table DemoTable (    ListOfNumbers varchar(100) ); Query OK, 0 rows affected (1.24 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('784, 746, 894, 344'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('456, 322, 333, 456'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('654, 785, 678, 456'); Query OK, 1 row affected (0.47 sec) mysql> insert into DemoTable values('123, 676, 847, 785'); Query OK, 1 row affected (0.34 ... Read More

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