To copy data from one field to another on every row, use the UPDATE command.Let us first create a table −mysql> create table DemoTable    (    StudentId int,    StudentFirstName varchar(20),    StudentMarks int default 0    ); Query OK, 0 rows affected (0.49 sec)Following is the query to insert records in the table using insert command −mysql> insert into DemoTable(StudentId, StudentFirstName) values(89, 'Larry'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable(StudentId, StudentFirstName) values(35, 'Robert'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable(StudentId, StudentFirstName) values(48, 'Chris'); Query OK, 1 row affected (0.13 sec) ... Read More

To retrieve records from the part of a comma-separated list, you can use built in function FIND_IN_SET().Let us first create a table −mysql> create table DemoTable    (    Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    Name varchar(20),    Marks varchar(200)    ); Query OK, 0 rows affected (0.61 sec)Following is the query to insert some records in the table using insert command −mysql> insert into DemoTable(Name, Marks) values('Larry', '98, 34, 56, 89'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable(Name, Marks) values('Chris', '67, 87, 92, 99'); Query OK, 1 row affected (0.15 sec) mysql> insert ... Read More

In MySQL, it is not possible to use select from procedure in FROM clause. You can use CALL command and after that the SELECT statement can be executed.Let us first create a table:mysql> create table DemoTable2    -> (    -> CustomerId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> CustomerName varchar(100),    -> ShippingDateTime datetime    -> ); Query OK, 0 rows affected (0.66 sec)Following is the query to create stored procedure:mysql> DELIMITER // mysql> CREATE PROCEDURE insert_information(Name varchar(100), shippingtime datetime)    -> BEGIN    ->    -> INSERT INTO DemoTable2(CustomerName, ShippingDateTime) VALUES(Name, shippingtime);    -> END    -> ... Read More

MySQL does not support array variables. To get the same result, use the table DUAL. Following is the syntax:SELECT yourValue1 AS ArrayValue FROM DUAL UNION ALL SELECT yourValue2 FROM DUAL UNION ALL SELECT yourValue3 FROM DUAL UNION ALL SELECT yourValue4 FROM DUAL UNION ALL . . . . . . SELECT yourValueN FROM DUAL;Let us create a sample table:mysql> SELECT 1 AS ArrayValue FROM DUAL       UNION ALL       SELECT 2 FROM DUAL       UNION ALL       SELECT 3 FROM DUAL       UNION ALL       SELECT 4 FROM ... Read More

To delete nth row in MySQL, use DELETE statement and work with subquery. Let us first create a table:mysql> create table DemoTable1    -> (    -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> StudentName varchar(100)    -> ); Query OK, 0 rows affected (0.99 sec)Following is the query to insert some records in the table using insert command:mysql> insert into DemoTable1(StudentName) values('Larry'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable1(StudentName) values('Sam'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable1(StudentName) values('Mike'); Query OK, 1 row affected (0.18 sec) mysql> ... Read More

Set the same condition like “OR” in a MySQL CASE expression. Let us first create a sample table.Following is the querymysql> create table caseOrConditionDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> Name varchar(100),    -> Score int    -> ); Query OK, 0 rows affected (0.49 sec)Following is the query to insert some records in the table using insert command:mysql> insert into caseOrConditionDemo(Name, Score) values('Larry', 85); Query OK, 1 row affected (0.18 sec) mysql> insert into caseOrConditionDemo(Name, Score) values('Sam', 74); Query OK, 1 row affected (0.20 sec) mysql> insert into caseOrConditionDemo(Name, ... Read More

The variable declaration must be between BEGIN and END. Under BEGIN and END, the first statement must be declaration of variable. After that you can include insert, select, etc.Let us now see an example. Here, the variable name is “output”:mysql> DELIMITER // mysql> CREATE PROCEDURE showVariablesValue() -> BEGIN -> DECLARE output varchar(100); -> SET output="Hello MySQL"; -> SELECT output; -> END -> // Query OK, 0 rows affected (0.25 sec) mysql> DELIMITER ;Now you can call the stored procedure using call ... Read More

Yes, MySQL internally convert bool to tinyint(1) because tinyint is the smallest integer data type.You can also say the bool is synonym for tinyint(1). Let us first create a sample table:mysql> create table boolToTinyIntDemo -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> Name varchar(20), -> isAgeGreaterThan18 bool -> ); Query OK, 0 rows affected (1.02 sec)Let us now check the description of table:mysql> desc boolToTinyIntDemo;This will produce the following output+--------------------+-------------+------+-----+---------+----------------+ | Field ... Read More

To select one specific row and another random row, you can use ORDER BY and RAND(). Let us first create a sample table:mysql> create table oneSpecificRowAndOtherRandom    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> Name varchar(20)    -> ); Query OK, 0 rows affected (0.72 sec)Following is the query to insert some records in the table using insert command:mysql> insert into oneSpecificRowAndOtherRandom(Name) values('Larry'); Query OK, 1 row affected (0.56 sec) mysql> insert into oneSpecificRowAndOtherRandom(Name) values('Sam'); Query OK, 1 row affected (0.13 sec) mysql> insert into oneSpecificRowAndOtherRandom(Name) values('Mike'); Query OK, 1 row affected ... Read More

In MySQL, AUTO_INCREMENT=3 tells that the inserted record will start from 3 not the default 1. Let us first create a sample table and set auto increment to 3:mysql> create table Auto_incrementDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> Name varchar(20)    -> )AUTO_INCREMENT=3; Query OK, 0 rows affected (0.52 sec)Following is the query to insert some records in the table using insert command:mysql> INSERT INTO Auto_incrementDemo(Name) values('John'); Query OK, 1 row affected (0.12 sec) mysql> INSERT INTO Auto_incrementDemo(Name) values('Larry'); Query OK, 1 row affected (0.15 sec) mysql> INSERT INTO Auto_incrementDemo(Name) ... Read More