sql declare variable
-- Declare the variable to be used.
DECLARE @MyCounter int;
-- Initialize the variable.
SET @MyCounter = 0;
sql declare variable
-- Declare the variable to be used.
DECLARE @MyCounter int;
-- Initialize the variable.
SET @MyCounter = 0;
sql declare table variable
DECLARE @TABLE TABLE( COL1 INT, COL2 VARCHAR(30))
how to declare a variable in sql
DECLARE @COURSE_ID AS INT, @COURSE_NAME VARCHAR (10);
declare value in sql
DECLARE { @LOCAL_VARIABLE[AS] data_type [ = value ] }
var in sql
One way of doing this is to use database variables
create table testcalc (
id int(11) not null auto_increment,
num1 int(11) default null,
num2 int(11) default null,
num3 int(11) default null,
num4 int(11) default null,
primary key(id)
);
insert into testcalc values
(default, 1, 2, 3, 4),
(default, 5, 10, 15, 20);
Then you can get the same results as in your example by storing the calculation results in variable syntax like this
@youVar := (calc) as resultName01
Then it will be available to following calculations to use like this
(@youVar + newCalc) as resultName02
We can apply it to your example like this
select
id,
num1,
num2,
num3,
num4,
@1plus2 := (num1 + num2) as 1plus2, # create var01
@1plus2mult3 := (@1plus2 * num3) as 1plus2mult3, # create var02 using var01
@sumOfCalc := (@1plus2 + @1plus2mult3) as sumOfCalc # create var03 using var01 and var02
from testcalc;
Copyright © 2021 Codeinu
Forgot your account's password or having trouble logging into your Account? Don't worry, we'll help you to get back your account. Enter your email address and we'll send you a recovery link to reset your password. If you are experiencing problems resetting your password contact us