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Found 6705 Articles for Database

4K+ Views
To insert current date to the database, you can use NOW(). Following is the syntax −INSERT INTO yourTableName(yourDateColumnName) VALUES(NOW());If your column has datatype date then NOW() function inserts only current date, not time and MySQL will give a warning. To remove the warning, you can use CURDATE().Let us first create a table −mysql> create table insertcurrentdate -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> currentDate date -> ); Query OK, 0 rows affected (1.09 sec)Following is the query to insert some records in the table using insert command. We have used both NOW() ... Read More

750 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

393 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

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

376 Views
The CAST() function in MySQL converts a value of any type into a value that has a specified type. Let us first create a table −mysql> create table castFunctionDemo -> ( -> ShippingDate date -> ); Query OK, 0 rows affected (0.74 sec)Following is the query to insert some records in the table using insert command −mysql> insert into castFunctionDemo values('2019-01-31'); Query OK, 1 row affected (0.20 sec) mysql> insert into castFunctionDemo values('2018-07-12'); Query OK, 1 row affected (0.16 sec) mysql> insert into castFunctionDemo values('2016-12-06'); Query OK, 1 row affected (0.16 sec) mysql> insert ... Read More

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

406 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

1K+ Views
To calculate a value from multiple columns, use GROUP BY. Following is the syntax −select yourColumnName1, sum(yourColumnName2*yourColumnName3) AS anyAliasName from yourTableName group by yourColumnName1;Let us first create a table −mysql> create table calculateValueDemo -> ( -> Id int, -> ProductPrice int, -> ProductWeight int -> ); Query OK, 0 rows affected (0.56 sec)Following is the query to insert records in the table using insert command −mysql> insert into calculateValueDemo values(100, 35, 5); Query OK, 1 row affected (0.16 sec) mysql> insert into calculateValueDemo values(101, 50, 3); Query OK, 1 row affected (0.16 sec) ... Read More

1K+ Views
To select distinct value from one column only, you can use aggregate function MAX() along with GROUP BY. Let us first create a table −mysql> create table distinctFromOneColumn -> ( -> StudentId int, -> StudentName varchar(100) -> ); Query OK, 0 rows affected (0.77 sec)Following is the query to insert records in the table using insert command −mysql> insert into distinctFromOneColumn values(1001, 'John'); Query OK, 1 row affected (0.15 sec) mysql> insert into distinctFromOneColumn values(1002, 'Carol'); Query OK, 1 row affected (0.15 sec) mysql> insert into distinctFromOneColumn values(1001, 'Sam'); Query OK, 1 row affected ... Read More

8K+ Views
This error occurs if let’s say you used var_char instead of varchar type. To remove this type of error, use, for example, varchar(100) instead of var_char(100).Let us now see how this error occurs −mysql> create table removeErrorDemo -> ( -> StudentId int, -> StudentName var_char(50) -> );The following is the output displaying the error −ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'var_char(50) )' at line 4Now let us remove the error. Here is the query ... Read More