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Found 6705 Articles for Database

1K+ Views
Here’s the syntax to check whether the table already exists using the CREATE TABLE IF NOT EXISTS −create table if not exists yourTableName ( yourColumnName1 dataType, . . . . N ); insert into yourTableName values(yourValue1, .......N);Let us first create a table −mysql> create table if not exists DemoTable ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentSubject varchar(100) ); Query OK, 0 rows affected (0.60 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(StudentSubject) values('Java'); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable(StudentSubject) values('MySQL'); ... Read More

135 Views
For this, you can use FIND_IN_SET(). Let us first create a table −mysql> create table DemoTable ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, Value varchar(100) ); Query OK, 0 rows affected (2.49 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(Value) values('100;200;300'); Query OK, 1 row affected (0.42 sec) mysql> insert into DemoTable(Value) values('1;300;400'); Query OK, 1 row affected (0.58 sec) mysql> insert into DemoTable(Value) values('6;7;8;9;10'); Query OK, 1 row affected (0.29 sec) mysql> insert into DemoTable(Value) values('1;2;3;4;5'); Query OK, 1 row affected (9.36 sec) mysql> insert into DemoTable(Value) values('3;8;9;10'); Query OK, 1 ... Read More

1K+ Views
Let us first create a table &mnus;mysql> create table DemoTable ( `timestamp` timestamp ); Query OK, 0 rows affected (1.12 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(now()); Query OK, 1 row affected (0.27 sec) mysql> insert into DemoTable values('00:00:00'); Query OK, 1 row affected (0.73 sec) mysql> insert into DemoTable values('2018-01-10 12:34:45'); Query OK, 1 row affected (0.80 sec) mysql> insert into DemoTable values('2019-12-31 10:50:45'); Query OK, 1 row affected (0.84 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+---------------------+ | timestamp ... Read More

426 Views
For this, you can use replace() along with group_concat(). Here, for empty fields, we are displaying a comma as a separator. Let us first create a table −mysql> create table DemoTable ( Id int, Number varchar(100) ); Query OK, 0 rows affected (2.03 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(10, '456'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values(11, '345'); Query OK, 1 row affected (0.28 sec) mysql> insert into DemoTable values(10, ''); Query OK, 1 row affected (0.63 sec) mysql> insert into DemoTable values(10, '278'); Query ... Read More

649 Views
For this, you can use ORDER BY DESC with LIMIT. Let us first create a table −mysql> create table DemoTable ( UserId int NOT NULL AUTO_INCREMENT PRIMARY KEY, UserName varchar(100) ); Query OK, 0 rows affected (0.59 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(UserName) values('Chris'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable(UserName) values('Robert'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable(UserName) values('Bob'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable(UserName) values('David'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable(UserName) ... Read More

331 Views
Let us first create a table −mysql> create table DemoTable ( Name varchar(100) ); Query OK, 0 rows affected (0.60 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John_Smith'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Chris Brown'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('John_Doe'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('David Miller'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Carol Taylor'); Query OK, 1 row affected (0.13 sec)Display all records from the table using select ... Read More

282 Views
For this, you can use DISTINCT along with the INSERT INTO SELECT statement. Let us first create a table −mysql> create table DemoTable1 ( Value int ); Query OK, 0 rows affected (1.03 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1 values(50); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable1 values(10); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable1 values(10); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable1 values(60); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable1 values(50); Query OK, 1 row ... Read More

1K+ Views
Let us first create a table −mysql> create table DemoTable ( UserId int, UserMessage varchar(100) ); Query OK, 0 rows affected (0.51 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(1, 'Hi'); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable values(2, 'Hello'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values(2, 'Good'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values(1, 'Nice'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable values(1, 'Awesome'); Query OK, 1 row affected (0.16 sec) mysql> insert ... Read More

1K+ Views
For this, you can use IN() along with ORDER BY FIELD(). Let us first create a table −mysql> create table DemoTable ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(100) ); Query OK, 0 rows affected (0.64 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(FirstName) values('Chris'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable(FirstName) values('Robert'); Query OK, 1 row affected (0.08 sec) mysql> insert into DemoTable(FirstName) values('Mike'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable(FirstName) values('Sam'); Query OK, 1 row affected (0.12 sec) mysql> insert into ... Read More

556 Views
Use information_schema.tables to display all the tables. With that, se the database name as well, so that you can display tables only from a specific database.Let us now display all the tables in the database “web” −mysql> select group_concat(table_name) from information_schema.tables where table_schema='web';This will produce the following output −+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | group_concat(table_name) | +------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | demo_table725, demotabe619, demotabe620, demotable211, demotable212, demotable213, demotable214, demotable215, demotable216, demotable217, demotable218, demotable219, demotable220, demotable221, demotable222, demotable223, demotable224, demotable225, demotable226, demotable227, demotable228, demotable229, demotable230, demotable231, demotable232, demotable233, demotable234, demotable235, demotable236, demotable237, demotable238, demotable239, demotable240, demotable241, demotable244, demotable245, demotable246, demotable247, demotable248, demotable249, demotable250, demotable251, demotable252, demotable 253, demotable254, ... Read More