Database Articles

Page 488 of 546

MySQL select only duplicate records from database and display the count as well?

Smita Kapse
Smita Kapse
Updated on 30-Jul-2019 436 Views

To select only duplicate records from database and display the count, use HAVING along with aggregate function count(). Let us first create a table −mysql> create table duplicateRecords    -> (    -> ClientId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> ClientName varchar(20)    -> ); Query OK, 0 rows affected (0.49 sec)Following is the query to insert records in the table using insert command −mysql> insert into duplicateRecords(ClientName) values('John'); Query OK, 1 row affected (0.16 sec) mysql> insert into duplicateRecords(ClientName) values('Carol'); Query OK, 1 row affected (0.17 sec) mysql> insert into duplicateRecords(ClientName) values('John'); Query OK, 1 row affected ...

Read More

How to compare timestamps in MySQL?

Nishtha Thakur
Nishtha Thakur
Updated on 30-Jul-2019 4K+ Views

To compare timestamps in MySQL, you can use DATE(). Let us first create a table−mysql> create table comparingTimestampDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> AdmissionDate timestamp    -> ); Query OK, 0 rows affected (0.54 sec)Following is the query to insert records in the table using insert command −mysql> insert into comparingTimestampDemo(AdmissionDate) values('2019-03-31'); Query OK, 1 row affected (0.13 sec) mysql> insert into comparingTimestampDemo(AdmissionDate) values('2019-04-10'); Query OK, 1 row affected (0.12 sec) mysql> insert into comparingTimestampDemo(AdmissionDate) values('2019-04-15'); Query OK, 1 row affected (0.17 sec) mysql> insert into comparingTimestampDemo(AdmissionDate) values('2019-03-29'); Query OK, 1 ...

Read More

Can we GROUP BY one column and select all data in MySQL?

Smita Kapse
Smita Kapse
Updated on 30-Jul-2019 1K+ Views

Yes, you can use group_concat() for this. Let us first create a table −mysql> create table groupByOneSelectAll    -> (    -> StudentDetails varchar(100),    -> StudentName varchar(100)    -> ); Query OK, 0 rows affected (0.91 sec)Following is the query to insert some records in the table using insert command −mysql> insert into groupByOneSelectAll values('StudentFirstName', 'John'); Query OK, 1 row affected (0.14 sec) mysql> insert into groupByOneSelectAll values('StudentFirstName', 'Chris'); Query OK, 1 row affected (0.21 sec) mysql> insert into groupByOneSelectAll values('StudentFirstName', 'Robert'); Query OK, 1 row affected (0.65 sec) mysql> insert into groupByOneSelectAll values('StudentFirstName', 'Bob'); Query ...

Read More

Add10 minutes to MySQL datetime format?\\n\\n

Nishtha Thakur
Nishtha Thakur
Updated on 30-Jul-2019 426 Views

Use DATE_ADD() to add 10 minutes to datetime format. Following is the syntax −select date_add(yourColumnName ,interval 10 minute) from yourTableName;Let us first create a table −mysql> create table add10MinuteDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> DelayDatetime datetime    -> ); Query OK, 0 rows affected (0.83 sec)Following is the query to insert records in the table using insert command −mysql> insert into add10MinuteDemo(DelayDatetime) values('2019-01-23 12:45:56'); Query OK, 1 row affected (0.16 sec) mysql> insert into add10MinuteDemo(DelayDatetime) values('2019-03-25 10:30:23'); Query OK, 1 row affected (0.19 sec) mysql> insert into add10MinuteDemo(DelayDatetime) values('2019-04-21 04:04:30'); Query ...

Read More

MySQL format time with lowercase am/pm?

Anvi Jain
Anvi Jain
Updated on 30-Jul-2019 805 Views

To format MySQL time with lowercase am/pm, use the LOWER() as well as DATE_FORMAT().Let us first create a table −mysql> create table formatTime    -> (    -> LoginTime time    -> ); Query OK, 0 rows affected (0.56 sec)Following is the query to insert records in the table using insert command −mysql> insert into formatTime values('12:40:34'); Query OK, 1 row affected (0.20 sec) mysql> insert into formatTime values('14:10:58'); Query OK, 1 row affected (0.13 sec) mysql> insert into formatTime values('16:56:40'); Query OK, 1 row affected (0.18 sec) mysql> insert into formatTime values('10:12:14'); Query OK, 1 row ...

Read More

Reorder integer except for value 0 with MySQL?

Anvi Jain
Anvi Jain
Updated on 30-Jul-2019 135 Views

To reorder integer except for value 0, use the below syntax −select *from yourTableName order by yourColumnName=0 ,yourColumnName;Let us first create a table −mysql> create table reorderIntegerExcept0    -> (    -> value int    -> ); Query OK, 0 rows affected (0.70 sec)Following is the query to insert records in the table using insert command −mysql> insert into reorderIntegerExcept0 values(90); Query OK, 1 row affected (0.17 sec) mysql> insert into reorderIntegerExcept0 values(10); Query OK, 1 row affected (0.21 sec) mysql> insert into reorderIntegerExcept0 values(0); Query OK, 1 row affected (0.18 sec) mysql> insert into reorderIntegerExcept0 values(40); ...

Read More

Select results from the middle of a sorted list in MySQL?

Smita Kapse
Smita Kapse
Updated on 30-Jul-2019 994 Views

To select results from the middle of a sorted list, use ORDER BY clause along with LIMIT.Let us first create a table. Following is the query −mysql> create table sortedListDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> StudentName varchar(100)    -> ); Query OK, 0 rows affected (0.46 sec)Following is the query to insert some records in the table using insert command −mysql> insert into sortedListDemo(StudentName) values('John'); Query OK, 1 row affected (0.62 sec) mysql> insert into sortedListDemo(StudentName) values('Sam'); Query OK, 1 row affected (0.18 sec) mysql> insert into sortedListDemo(StudentName) values('Adam'); ...

Read More

Difference between count(*) and count(columnName) in MySQL?

George John
George John
Updated on 30-Jul-2019 3K+ Views

The count(*) returns all rows whether column contains null value or not while count(columnName) returns the number of rows except null rows.Let us first create a table.Following is the querymysql> create table ifNotNullDemo    -> (    -> Name varchar(20)    -> ); Query OK, 0 rows affected (0.54 sec)Following is the query to insert some records in the table using insert command:mysql> insert into ifNotNullDemo values('Chris'); Query OK, 1 row affected (0.15 sec) mysql> insert into ifNotNullDemo values(''); Query OK, 1 row affected (0.13 sec) mysql> insert into ifNotNullDemo values('Robert'); Query OK, 1 row affected (0.24 sec) ...

Read More

Resolve Unknown database in JDBC error with Java-MySQL?\\n

George John
George John
Updated on 30-Jul-2019 9K+ Views

This type of error occurs if you select any database that does not exist in MySQL. Let us first display the error of unknown database in JDBC.The Java code is as follows. Here, we have set the database as ‘onlinebookstore’, which does not exist:import java.sql.Connection; import java.sql.DriverManager; public class UnknownDatabaseDemo {    public static void main(String[] args) {       String JdbcURL = "jdbc:mysql://localhost:3306/onlinebookstore?useSSL=false";       String Username = "root";       String password = "123456";       Connection con = null;       try {          con = DriverManager.getConnection(JdbcURL, Username, password); ...

Read More

Can we order a MySQL result with mathematical operations?\\n

George John
George John
Updated on 30-Jul-2019 311 Views

Yes, we can order with mathematical operations using ORDER BY clause. Let us first create a table:mysql> create table orderByMathCalculation    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> Quantity int,    -> Price int    -> ); Query OK, 0 rows affected (0.57 sec)Following is the query to insert some records in the table using insert command:mysql> insert into orderByMathCalculation(Quantity, Price) values(10, 50); Query OK, 1 row affected (0.21 sec) mysql> insert into orderByMathCalculation(Quantity, Price) values(20, 40); Query OK, 1 row affected (0.14 sec) mysql> insert into orderByMathCalculation(Quantity, Price) values(2, 20); Query ...

Read More
Showing 4871–4880 of 5,456 articles
« Prev 1 486 487 488 489 490 546 Next »
Advertisements