Found 4378 Articles for MySQL

MySQL select count by value?

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

90 Views

You can use COUNT() function for this. Let us first create a demo tablemysql> create table countValueDemo -> ( -> ShippingDatetime datetime, -> FirstValue int, -> SecondValue int -> ); Query OK, 0 rows affected (1.35 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into countValueDemo values('2019-01-23', 1, 2); Query OK, 1 row affected (0.24 sec) mysql> insert into countValueDemo values('2017-02-21', NULL, 2); Query OK, 1 row affected (0.13 sec) mysql> insert into countValueDemo values('2016-04-12', 1, NULL); ... Read More

How to fasten MySQL inserts?

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

90 Views

You can speed the MySQL insert when you are inserting multiple records at the same time with the help of the following syntaxSTART TRANSACTION insert into insertDemo(yourColumnName1, yourColumnName2, ...N) values(yourValue1, yourValue2, ....N), (yourValue1, yourValue2, ....N), .......N commitLet us first create a demo tablemysql> create table insertDemo    -> (    -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> StudentName varchar(20),    -> StudentAge int    -> ); Query OK, 0 rows affected (0.72 sec)Insert multiple records at the same time. The query is as follows −mysql> START TRANSACTION; Query OK, 0 rows affected (0.00 sec) mysql> insert into ... Read More

Exclude certain columns from SHOW COLUMNS in MySQL?

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

233 Views

Let us first create a demo tablemysql> create table excludeCertainColumnsDemo    -> (    -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> StudentName varchar(100),    -> StudentAge int,    -> StudentMarks int,    -> StudentAddress varchar(200)    -> ); Query OK, 0 rows affected (0.50 sec)Now you can check the description of table with the help of desc command. The query is as follows −mysql> desc excludeCertainColumnsDemo;The following is the output+----------------+--------------+------+-----+---------+----------------+ | Field          | Type         | Null | Key | Default | Extra          | +----------------+--------------+------+-----+---------+----------------+ | ... Read More

Convert MySQL Unix-Timestamp format to date format?

Arjun Thakur
Updated on 30-Jul-2019 22:30:25

526 Views

To achieve this, the following is the syntaxselect date_format(from_unixtime(yourColumnName), '%b %d, %Y %l:%i %p PDT') from yourTableName;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table unixTimeStampFormatDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> MyTimeStampValue bigint    -> ); Query OK, 0 rows affected (0.59 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into unixTimeStampFormatDemo(MyTimeStampValue) values(1334428200); Query OK, 1 row affected (0.20 sec) mysql> insert into unixTimeStampFormatDemo(MyTimeStampValue) values(1513881000); Query OK, 1 row affected (0.15 ... Read More

Order by a function of two columns in a single MySQL query

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

70 Views

Let us first create a tablemysql> create table orderByAFunctionDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> FirstNumber int,    -> SecodNumber int    -> ); Query OK, 0 rows affected (0.44 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into orderByAFunctionDemo(FirstNumber, SecodNumber) values(10, 4); Query OK, 1 row affected (0.11 sec) mysql> insert into orderByAFunctionDemo(FirstNumber, SecodNumber) values(45, 78); Query OK, 1 row affected (0.17 sec) mysql> insert into orderByAFunctionDemo(FirstNumber, SecodNumber) values(23, 10); Query OK, 1 row affected (0.12 sec) mysql> insert into orderByAFunctionDemo(FirstNumber, SecodNumber) values(67, ... Read More

Display sum in last row of table using MySQL?

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

1K+ Views

To display sum in last row of a table, you can use UNION. To understand how, let us create a tablemysql> create table showSumInLastRowDemo    -> (    -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> StudentName varchar(20),    -> StudentMarks int    -> ); Query OK, 0 rows affected (0.69 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into showSumInLastRowDemo(StudentName, StudentMarks) values('John', 56); Query OK, 1 row affected (0.14 sec) mysql> insert into showSumInLastRowDemo(StudentName, StudentMarks) values('John', 87); Query OK, 1 row affected (0.10 sec) mysql> insert into showSumInLastRowDemo(StudentName, StudentMarks) ... Read More

How to compare two strings which are numbers in MySQL?

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

901 Views

To compare two strings which are numbers in MySQL, use the CAST() function.The syntax is as followsselect *from yourTableName where cast(yourColumnName as signed)=yourIntegerValue;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table compareTwoStringDemo -> ( -> UserId varchar(100) -> ); Query OK, 0 rows affected (0.78 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into compareTwoStringDemo values('1083745'); Query OK, 1 row affected (0.12 sec) mysql> insert into compareTwoStringDemo values('9867585'); Query OK, 1 ... Read More

Add new MySQL table columns and create indexes?

Arjun Thakur
Updated on 30-Jul-2019 22:30:25

138 Views

To add a new MySQL table column and index, you can use ALTER TABLE command.The syntax is as followsALTER TABLE yourTableName ADD COLUMN yourColumnName dataType, ADD INDEX(yourColumnName );To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table AddColumnAndIndexDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> Name varchar(100),    -> Address varchar(200)    -> ); Query OK, 0 rows affected (0.81 sec)Now you can check the description of table. The query is as follows −mysql> desc AddColumnAndIndexDemo;The following is the output+---------+--------------+------+-----+---------+----------------+ | Field ... Read More

How to find absolute difference between two numbers in MySQL?

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

3K+ Views

To get the difference between two number in MySQL, let us first create a demo tablemysql> create table findDifferenceDemo -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> FirstNumber float, -> SecondNumber float -> ); Query OK, 0 rows affected (0.60 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into findDifferenceDemo(FirstNumber, SecondNumber) values(4.2, 2.3); Query OK, 1 row affected (0.20 sec) mysql> insert into findDifferenceDemo(FirstNumber, SecondNumber) values(23.4, 5.6); Query OK, 1 row affected (0.14 sec) ... Read More

How to select unique value in MySQL?

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

2K+ Views

You can select unique value with the help of DISTINCT keyword.The syntax is as followsselect distinct yourColumnName from yourTableName;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table selectUniqueValue -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> Name varchar(20), -> Age int -> ); Query OK, 0 rows affected (0.64 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into selectUniqueValue(Name, Age) values('John', 21); ... Read More

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