Found 4381 Articles for MySQL

Extracting filenames from a path in MySQL?

Samual Sam
Updated on 30-Jul-2019 22:30:25

667 Views

To extract filenames from a path MySQL, you can use SUBSTRING_INDEX(). The syntax is as follows −SELECT SUBSTRING_INDEX(ypurColumnName, '\', -1) as anyAliasName FROM yourTableName;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table ExtractFileNameDemo -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> AllProgrammingFilePath varchar(100) -> ); Query OK, 0 rows affected (0.50 sec)Now you can insert some records in the table using insert command. The query is as follows −mysql> insert into ExtractFileNameDemo(AllProgrammingFilePath) ... Read More

Is there a built-in function for week of the month in MySQL?

karthikeya Boyini
Updated on 30-Jul-2019 22:30:25

850 Views

There is no standard function to get week of month in MySQL. You need to use the following syntax −SELECT WEEK(yourDateColumnName, 5) - WEEK(DATE_SUB(yourDateColumnName, INTERVAL DAYOFMONTH(yourDateColumnName) - 1 DAY), 5) + 1 AS anyAliasName FROM yourTableName;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table FirstWeekOfMonth -> ( -> Id int NOT NULL AUTO_INCREMENT primary key, -> yourdate date -> ); Query OK, 0 rows affected (2.50 sec)Now you can insert some records in the table ... Read More

Sort certain values to the top in MySQL?

Samual Sam
Updated on 30-Jul-2019 22:30:25

258 Views

You need to use ORDER BY clause to sort. The syntax is as follows −SELECT *FROM yourTableName ORDER BY yourColumnName='yourValue' DESC, yourIdColumnName;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table SortCertainValues    -> (    -> Id int NOT NULL AUTO_INCREMENT,    -> Name varchar(20),    -> CountryName varchar(10),    -> PRIMARY KEY(Id)    -> ); Query OK, 0 rows affected (1.36 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into SortCertainValues(Name, CountryName) values('Adam', 'US'); Query OK, 1 row ... Read More

Can I use InnoDB and MyISAM tables in a single database in MySQL?

karthikeya Boyini
Updated on 30-Jul-2019 22:30:25

564 Views

Yes, you can use InnoDB and MyISAM tables in one database or combine both of them in a single database. This is the recommended way.Here is the demo of both MyISAM and InnoDB in a one database. The following is the database and both the table types InnoDB and MyISAM. The query to create a database is as follows −mysql> create database BothInnoDBandMyISAM; Query OK, 1 row affected (0.20 sec) mysql> use BothInnoDBandMyISAM; Database changedI have a database with name ‘BothInnoDBandMyISAM’.First the table has engine type InnoDB. The query to create a table with engine InnoDB is as follows −mysql> ... Read More

How do I cast a type to a BigInt in MySQL?

Samual Sam
Updated on 30-Jul-2019 22:30:25

6K+ Views

You need to use the CAST operator along with CONV() function. The CONV() function can be used to convert one base number system to another base system.For Example, The 16 is one base system and 10 is another base system. The 16 base system is hexadecimal and 10 is a decimal.The syntax is as follows −SELECT CAST(CONV('yourColumnName', 16, 10) AS UNSIGNED INTEGER) as anyAliasName FROM yourTableName;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table castTypeToBigIntDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT,     ... Read More

How do I update the decimal column to allow more digits in MySQL?

Chandu yadav
Updated on 30-Jul-2019 22:30:25

2K+ Views

To update the decimal column to allow more digit, use the MODIFY COLUMN. The syntax is as follows:ALTER TABLE MODIFY COLUMN yourColumnName DECIMAL(yourIntValue, yourIntValue);To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table allowDecimalWithMoreDigit    -> (      -> Id int NOT NULL AUTO_INCREMENT,    -> Salary DECIMAL(3, 2),    -> PRIMARY KEY(Id)    -> ); Query OK, 0 rows affected (0.64 sec)Now you can check the description of table using DESC command. The syntax is as follows:DESC yourTableName;Now you can check the description of table using above ... Read More

MySQL: What is 'AUTO_INCREMENT=5' in a create table query?

Arjun Thakur
Updated on 30-Jun-2020 13:13:09

828 Views

The AUTO_INCREMENT=5 in a create table query tells that the first record will start from 5 i.e. not default 1. As we know if you do not set the value to AUTO_INCREMENT then MySQL starts from 1 by default.The syntax is as follows:CREATE TABLE yourTableName ( yourColumnName1 dataType NOT NULL AUTO_INCRMENT, . . . N, PRIMARY KEY(yourColumnName1 ) )AUTO_INCREMENT=5;To understand the above syntax, let us create a table.Case1 − The table starts auto increment from 1 because it is the default standard.The query to create a table is as follows:mysql> create table defaultAutoIncrementDemo    -> (    -> Id int ... Read More

Adding a column whose value is not null by default in MySQL?

Ankith Reddy
Updated on 30-Jul-2019 22:30:25

1K+ Views

For this, you need to remove the default keyword. The syntax is as follows:ALTER TABLE yourTableName ADD COLUMN yourColumnName dataType NOT NULL AFTER yourColumnName;To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table AddingColumnDefaultValueNOTNULL    -> (    -> Id int NOT NULL AUTO_INCREMENT,    -> FirstName varchar(20),    -> LastName varchar(20),    -> Age int,    -> Address varchar(100),    -> Salary int,    -> PRIMARY KEY(Id)    -> ); Query OK, 0 rows affected (0.58 sec)Now check the description of table. The query is as follows:mysql> desc ... Read More

Reset MySQL field to default value?

George John
Updated on 30-Jul-2019 22:30:25

2K+ Views

In MySQL, there are two approaches by which you can reset the MySQL field to default value. One is default keyword and another is default() function.Case 1: Using default keyword. The syntax is as follows:UPDATE yourTableName SET yourColumnName=default where yourCondition;Case 2: Using default() function. The syntax is as follows:UPDATE yourTableName SET yourColumnName=default(yourColumnName) where yourCondition;To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table Default_Demo    -> (    -> Id int NOT NULL AUTO_INCREMENT,    -> Name varchar(20),    -> Age int,    -> Salary float,    -> PRIMARY ... Read More

Can we select row by DATEPART() in MySQL? Is it possible?

Chandu yadav
Updated on 30-Jul-2019 22:30:25

2K+ Views

There is no DATEPART() function in MySQL, you need to use MONTH() function to extract the month name from date column. The syntax is as follows:SELECT *FROM yourTableName WHERE MONTH(yourDateColumnName)=yourValue;To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table SelectRowFromDatePart -> ( -> Id int NOT NULL AUTO_INCREMENT, -> LoginDate date, -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (2.42 sec)Now you can insert some records in the table using ... Read More

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