- Trending Categories
Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Found 4378 Articles for MySQL
![Samual Sam](https://www.tutorialspoint.com/assets/profiles/13514/profile/60_83486-1512649303.jpg)
548 Views
To get the column name on the result set, you need to use getMetaData() method. The prototype of getMetadata() is as follows −ResultSetMetaData getMetaData throws SQLException;Create a MySQL table with 5 column names. The query to create a table is as follows −mysql> create table javagetallcolumnnames -> ( -> Id int NOT NULL AUTO_INCREMENT, -> Name varchar(20), -> Age int, -> Salary float, -> Address varchar(100), -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (1.34 sec)The following is the Java code that gets the column name on ResultSet. The code ... Read More
![Arjun Thakur](https://www.tutorialspoint.com/assets/profiles/13574/profile/60_74441-1560315595.jpg)
955 Views
If your cast does not work, then you can use yourColumnName*1 with ORDER BY clause.Using yourColumnName*1. The syntax is as follows:SELECT yourColumnName1, yourColumnName2, ...N FROM yourTableName ORDER BY yourColumnName*1 DESC;You can also use CAST() operator. The syntax is as follows:SELECT yourColumnName1, yourColumnName2, ...N FROM yourTableName ORDER BY CAST(yourColumnName as DECIMAL(8, 2)) DESC;To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table VarcharColumnAsFloatDemo -> ( -> Id int NOT NULL AUTO_INCREMENT, -> Amount varchar(20), -> PRIMARY KEY(Id) ... Read More
![Ankith Reddy](https://www.tutorialspoint.com/assets/profiles/22328/profile/60_142162-1519038074.jpg)
1K+ Views
To find rows and update with new value where column value ends with specific substring you need to use LIKE operator.The syntax is as follows:UPDATE yourTableName SET yourColumnName=’yourValue’ WHERE yourColumnName LIKE ‘%.yourString’;To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table RowEndsWithSpecificString -> ( -> Id int NOT NULL AUTO_INCREMENT, -> FileName varchar(30), -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (1.50 sec)Now you can insert some records in the table using ... Read More
![George John](https://www.tutorialspoint.com/assets/profiles/13511/profile/60_58410-1512537824.png)
501 Views
To fetch rows where first character is not alphanumeric, you can use the following regular expression.Case 1 − If you want those rows that starts from a digit, you can use the following syntax −SELECT *FROM yourTableName WHERE yourColumnName REGEXP '^[0-9]';Case 2 − If you want those rows that start from an alphanumeric, use the following syntax −SELECT *FROM yourTableName WHERE yourColumnName REGEXP '^[^0-9A-Za-z]' ;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table getRowsFirstNotAlphanumeric -> ( -> Id int NOT NULL AUTO_INCREMENT, -> UserPassword varchar(20), -> PRIMARY ... Read More
![Chandu yadav](https://www.tutorialspoint.com/assets/profiles/22330/profile/60_142811-1519038104.jpg)
18K+ Views
If you want to get only digits using REGEXP, use the following regular expression( ^[0-9]*$) in where clause.Case 1 − If you want only those rows which have exactly 10 digits and all must be only digit, use the below regular expression.SELECT *FROM yourTableName WHERE yourColumnName REGEXP '^[0-9]{10}$';Case 2 − If you want only those rows with the digit either 1 or more, the following is the syntax −SELECT *FROM yourTableName WHERE yourColumnName REGEXP '^[0-9]*$';The above syntax will give only those rows that do not have any any characters.To understand the above syntax, let us create a table. The query ... Read More
![Arjun Thakur](https://www.tutorialspoint.com/assets/profiles/13574/profile/60_74441-1560315595.jpg)
413 Views
Order by date and set the empty dates in the last with the help of ORDER BY clause and IS NULL property. The syntax is as follows:SELECT *FROM yourTableName ORDER BY (yourDateColumnName IS NULL), yourDateColumnName DESC;In the above syntax, we will sort the NULL first after that date. To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table DateColumnWithNullDemo -> ( -> Id int NOT NULL AUTO_INCREMENT, -> LoginDateTime datetime, -> PRIMARY KEY(Id) -> ... Read More
![Ankith Reddy](https://www.tutorialspoint.com/assets/profiles/22328/profile/60_142162-1519038074.jpg)
876 Views
The function TIME_TO_SEC() can be used in MySQL. If you want to convert datetime to seconds use the strtotime() from PHP. The MySQL syntax is as follows:SELECT TIME_TO_SEC(ABS(timediff(‘yourDateTimeValue’, now())));Now you can convert PHP datetime to seconds with the help of strtotime().First, you need to install XAMPP server to run your PHP program.After installing XAMPP successfully in C drive, here is the location wherein you need to include the PHP file. The snapshot is as follows:Note: Here, I have changed port of Apache to 8086 because default port was held by another program. This is done to begin running PHP program.Therefore, ... Read More
![George John](https://www.tutorialspoint.com/assets/profiles/13511/profile/60_58410-1512537824.png)
19K+ Views
You can remove special characters from a database field using REPLACE() function. The special characters are double quotes (“ “), Number sign (#), dollar sign($), percent (%) etc.The syntax is as follows to remove special characters from a database field.UPDATE yourTableName SET yourColumnName=REPLACE(yourColumnName, ’yourSpecialCharacters’, ’’);To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table RemoveSpecialCharacterDemo -> ( -> Id int NOT NULL AUTO_INCREMENT, -> Name varchar(20), -> PRIMARY Key(Id) -> ); Query OK, 0 rows affected (0.59 sec)Insert some records in the table using ... Read More
![Chandu yadav](https://www.tutorialspoint.com/assets/profiles/22330/profile/60_142811-1519038104.jpg)
525 Views
To find the nth highest value of a column, you need to use ORDER BY DESC with LIMIT clause. If you want the second highest value of a column, use the below syntax:SELECT *FROM yourTableName ORDER BY DESC yourColumnName LIMIT 1, 1;If you want the fourth highest value of a column, use the below syntax:SELECT *FROM yourTableName ORDER BY DESC yourColumnName LIMIT 3, 1;If you want the first highest value of a column, use the below syntax:SELECT *FROM yourTableName ORDER BY DESC yourColumnName LIMIT 1;As discussed in the above syntax, you need to change only in LIMIT clause. To understand ... Read More
![Arjun Thakur](https://www.tutorialspoint.com/assets/profiles/13574/profile/60_74441-1560315595.jpg)
5K+ Views
This error can occur if you try to set data higher than the allowed limit. As an example, you cannot store a string in a column of type bit because varchar or string takes size higher than bit data type.You need to use the following syntax for bit type column:anyBitColumnName= b ‘1’ OR anyBitColumnName= b ‘0’To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table IncasesensitiveDemo -> ( -> Id int NOT NULL AUTO_INCREMENT, -> Name varchar(10), -> PRIMARY KEY(Id) -> ); Query OK, ... Read More