Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Database Articles
Page 408 of 547
Filter dates from a table with DATE and NULL records in MySQL
Let us first create a table −mysql> create table DemoTable ( FirstDate datetime, SecondDate datetime ); Query OK, 0 rows affected (0.57 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('2019-01-21', '2018-01-21'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('2019-10-04', '2019-08-14'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('2019-05-01', '2019-09-11'); Query OK, 1 row affected (0.65 sec) mysql> insert into DemoTable values(NULL, NULL); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values('2019-03-01', NULL); Query OK, 1 row affected (0.13 sec)Display all records ...
Read MoreDynamically choosing a column in MySQL?
First, you need to prepare a query and then you need to execute the PREPARED statement to dynamically choose a column in MySQL.Let us first create a table −mysql> create table DemoTable ( EmployeeName varchar(100) ); Query OK, 0 rows affected (0.77 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John Doe'); Query OK, 1 row affected (0.18 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+--------------+ | EmployeeName | +--------------+ | John Doe | +--------------+ 1 row in set ...
Read MoreHow to filter dates in MySQL to fetch date record only for a specific month?
Let us first create a table −mysql> create table DemoTable ( AdmissionDate varchar(100) ); Query OK, 0 rows affected (1.06 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('2018-01-21'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('2019-08-13'); Query OK, 1 row affected (0.56 sec) mysql> insert into DemoTable values('2019-07-08'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('2016-02-12'); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+---------------+ | AdmissionDate | +---------------+ ...
Read MoreMySQL GROUP BY and CONCAT() to display distinct first and last name
Let us first create a table −mysql> create table DemoTable ( FirstName varchar(100), LastName varchar(100) ); Query OK, 0 rows affected (0.92 sec) mysql> alter table DemoTable add index(FirstName, LastName); Query OK, 0 rows affected (1.00 sec) Records: 0 Duplicates: 0 Warnings: 0Insert some records in the table using insert command −mysql> insert into DemoTable values('Adam', 'Smith'); Query OK, 1 row affected (0.73 sec) mysql> insert into DemoTable values('Adam', 'Smith'); Query OK, 1 row affected (1.17 sec) mysql> insert into DemoTable values('John', 'Doe'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('Carol', 'Taylor'); Query OK, ...
Read MoreSelect distinct names from two columns in MySQL and display the result in a single column
For this, use UNION. Let us first create a table −mysql> create table DemoTable ( Name1 varchar(100), Name2 varchar(100) ); Query OK, 0 rows affected (0.58 sec)Insert some records in the table using insert commandmysql> insert into DemoTable values('Adam', 'Bob'); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable values('Adam', 'Bob'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('David', 'Chris'); Query OK, 1 row affected (0.13 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+-------+-------+ | Name1 | Name2 | +-------+-------+ | ...
Read MoreUpdate 'a' record with 'b' and 'b' with 'a' in a MySQL column (swap) with only 'a' and 'b' values?
For this, use a CASE statement. Let us first create a table −mysql> create table DemoTable ( Value char(1) ); Query OK, 0 rows affected (1.21 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('a'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('b'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('a'); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable values('a'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('b'); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable ...
Read MoreCan we use INTERVAL keyword while inserting date records in a MySQL table?
Yes, we can use INTERVAL while inserting data records. Let us first create a table −mysql> create table DemoTable ( ArrivalTime datetime ); Query OK, 0 rows affected (0.52 sec)Insert some records in the table using insert command. Here, we are using INTERVAL keyword for incrementing the date records while inserting −mysql> insert into DemoTable values(date_add(now(), interval 4 hour)); Query OK, 1 row affected (0.41 sec) mysql> insert into DemoTable values(date_add('2016-01-31 10:40:50', interval 2 hour)); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values(date_add('2015-05-01 12:00:00', interval 1 hour)); Query OK, 1 row affected (0.25 sec) mysql> ...
Read MoreCan we use "year" as a column came in a MySQL Table?
Yes, you can give the year as a column name in MySQL table since it isn’t a reserved word. Let us first create a table −mysql> create table DemoTable ( Year int ); Query OK, 0 rows affected (0.87 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(1995); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values(2019); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values(2016); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values(2018); Query OK, 1 row affected (0.13 sec)Display all records from ...
Read MoreConcatenate rows on the basis of boolean values in another column with MySQL
To concatenate rows on the basis of boolean value in another column, use GROUP_CONCAT(). Let us first create a table. Here, we have set one of the columns “isValidUser” as BOOLEAN −mysql> create table DemoTable ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, UserMessage varchar(100), isValidUser boolean ); Query OK, 0 rows affected (0.63 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(UserMessage, isValidUser) values('Hi', true); Query OK, 1 row affected (0.26 sec) mysql> insert into DemoTable(UserMessage, isValidUser) values('Hello', false); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable(UserMessage, isValidUser) values('Good', ...
Read MoreMySQL ORDER BY letters (not numbers) for column values comprising strings with numbers like '456 John Smith'
To ORDER BY letters, use ORDER BY SUBSTRING(). Let us first create a table −mysql> create table DemoTable ( Id varchar(100) ); Query OK, 0 rows affected (0.65 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('456 John Smith'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('897 Adam Smith'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('1009 Bob Smith'); Query OK, 1 row affected (0.13 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+----------------+ | Id ...
Read More