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MySQL query to check if multiple rows exist?

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 846 Views

Let us first create a table −mysql> create table DemoTable1219 (    Id int,    Name varchar(40) ); Query OK, 0 rows affected (0.43 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1219 values(100, 'Adam'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable1219 values(101, 'John'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable1219 values(102, 'Chris'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable1219 values(103, 'Bob'); Query OK, 1 row affected (0.18 sec)Display all records from the table using select statement −mysql> select *from DemoTable1219;This will produce the ...

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Increment multiple Timestamp values by setting the incremented value in a user-defined variable in SQL

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 333 Views

The incremented value can be set in a user-defined variable as shown below. Here, “yourValue” is the incremented value. After that, use MySQL UPDATE to update the column and increment timestamp values −set @anyVariableName :=yourValue; update yourTableName set yourColumnName=yourColumnName+interval (@yourVariableName) second;Let us first create a table −mysql> create table DemoTable (    DueDatetime timestamp ); Query OK, 0 rows affected (0.73 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('2019-01-31 12 :30 :40'); Query OK, 1 row affected (0.25 sec) mysql> insert into DemoTable values('2019-09-06 10 :00 :00'); Query OK, 1 row affected (0.73 sec) ...

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Implement case sensitivity in MySQL SELECT statements

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 333 Views

SELECT is by default case-insensitive. For case-sensitive implementation, the BINARY operator is used. Following is the syntax :select *from yourTableName where BINARY yourColumnName=yourValue;Let us first create a table −mysql> create table DemoTable (    Name varchar(40) ); Query OK, 0 rows affected (0.74 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('CHRIS'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('chris'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('CHris'); Query OK, 1 row affected (0.11 sec)Display ...

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How to ORDER BY grouped fields in MySQL?

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 174 Views

To ORDER BY grouped fields, use ORDER BY CASE along with IN(). CASE evaluates different conditions whereas ORDER BY sort values in ascending or descending order. The MySQL IN() is used to find a match.Let us first create a table −mysql> create table DemoTable (    Value varchar(40) ); Query OK, 0 rows affected (0.52 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable values('100&101'); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable values('Sam'); Query OK, 1 row affected (0.09 sec) ...

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How to check if value exists with MySQL SELECT 1?

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 427 Views

Use SELECT 1 for this as in the below syntax −select 1 from yourTableName where yourColumnName=yourValue;If the above returns 1, that means value exists in the MySQL database. Let us first see an example and create a table −mysql> create table DemoTable (    StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    StudentName varchar(40),    StudentAge int ); Query OK, 0 rows affected (0.46 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(StudentName, StudentAge) values('Chris', 21); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable(StudentName, StudentAge) values('David', 20); Query OK, 1 row affected (0.16 ...

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MySQL CASE statement to place custom values in place of NULL

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 230 Views

Let us first create a table −mysql> create table DemoTable (    FirstName varchar(20) ); Query OK, 0 rows affected (1.15 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(NULL); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Adam'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(NULL); Query OK, 1 row affected (0.09 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+-----------+ | FirstName | +-----------+ ...

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MySQL query to return multiple row records with AND & OR operator

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 524 Views

Let us first create a table −mysql> create table DemoTable (    StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    StudentName varchar(40),    StudentMathMarks int,    StudentMySQLMarks int,    status ENUM('ACTIVE', 'INACTIVE') ); Query OK, 0 rows affected (0.47 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(StudentName, StudentMathMarks, StudentMySQLMarks, status) values('Chris', 45, 67, 'active'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable(StudentName, StudentMathMarks, StudentMySQLMarks, status) values('Bob', 89, 78, 'inactive'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable(StudentName, StudentMathMarks, StudentMySQLMarks, status) values('David', 56, 68, 'active'); Query OK, 1 row affected ...

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Difference between BIGINT and BIGINT(20) in MySQL?

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 4K+ Views

The only difference between BIGINT and BIGINT(20) is for displaying width. The 20 can be used for displaying width.Let us see an example and create a table. Here, we have set BIGINT(20) −mysql> create table DemoTable (    Number bigint(20) zerofill ); Query OK, 0 rows affected (0.58 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(1); Query OK, 1 row affected (0.08 sec) mysql> insert into DemoTable values(12); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values(123); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values(1234); Query OK, ...

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How to use MySQL LIKE clause to fetch multiple values beginning with "Joh

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 245 Views

Let us first create a table −mysql> create table DemoTable (    Name varchar(40) ); Query OK, 0 rows affected (0.55 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('Sam'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Mike'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('Ethan'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('Johnson'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Bob'); Query OK, 1 row affected ...

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Get left part of the string on the basis of last occurrence of delimiter in MySQL?

AmitDiwan
AmitDiwan
Updated on 07-Oct-2019 242 Views

For this, use LEFT() method. For manipulation, we have used the LOCATE() and the REVERSE() method.Let us first create a table −mysql> create table DemoTable (    Title text ); Query OK, 0 rows affected (0.52 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('$/This$is[MySQL]$/MySQL[FirstClass]$MySQL[SecondClass]'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('$/This$is[Java]$/Java[FirstClass]$Java[SecondClass]'); Query OK, 1 row affected (0.10 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+--------------------------------------------------------+ | Title                       ...

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