Can you please let me know if stored procedure allow to handle compound condition as below:
if(
( (select Count(*) from dbo.Membership where EmailID=#emailID) >0)
||
((select Count(*) from dbo.Allocation where ResourceEmail=#emailID)>0))
)
Use OR instead of ||
More optimal if just checking for existence, I'd use EXISTS instead of COUNT as it will stop when it first the first existence, instead of counting them all...
IF EXISTS(SELECT 1 FROM dbo.Membership WHERE EmailId = #emailID)
OR EXISTS(SELECT 1 FROM dbo.Allocation where ResourceEmail=#emailID)
BEGIN
-- emailID exists in one of the 2 tables
END
Related
In MySQL, is it possible to have two CASE statements in the SELECT clause, where the second CASE statement relies on the first CASE statement?
For example, consider the following query:
SELECT CASE WHEN `user`.`id` < 500 THEN 'awesome' ELSE 'lame' END
AS `status`
, CASE WHEN `status` = 'awesome' THEN 'You rock' ELSE 'You stink' END
AS `message`
FROM `user`
Basically, the user ID determines the status, and then the status determines the message.
However, as you might have guessed, this query generates this error:
Unknown column 'status'
The only solution I have found so far is two generate a temporary table, view, or subquery, and then the message is determined by the status returned in this subquery.
Is there a way to write this query without the use of a temporary table, view or subquery? I'm trying to avoid these constructs to keep the query simple and optimized if possible. Thank you!
You can, using temporary variables:
select
#status1 := (case
when user.id < 500 then 'awesome'
else 'lame'
end) as `status`,
(case
when #status1 = 'awesome' then 'You rock'
else 'You stink'
end) as message
from
user;
Some things you must know about temp variables:
They are always preceded by #
Avoid using reserved words, just in case (that's the reason I named the variable #status1
After the # symbol, they must begin with a letter, and must not have spaces
When you update them in a single query, they are updated "left-to-right" (talking about columns) and "first-to-last" (talking about rows). That can help you calculate cummulative sums or averages.
Example (for point 2):
select #t := 1, #t := #t + 1;
#t1 | #t2
----+----
1 | 2
Example (for point 3):
select myTable.x, #t := #t + myTable.x as cummulative_x
from
(select #t := 0) as init, -- You need to initialize the variable,
-- otherwise the results of the evaluation will be NULL
myTable
order by myTable.x -- Always specify how to order the rows,
-- or the cummulative values will be quite odd
-- (and maybe not what you want)
;
x | cummulative_x
---+---------------
1 | 1
1 | 2
2 | 4
3 | 7
Temporary variables can help you do some awesome things... feel free to play around ;)
Update
If you want to define conditions on the result of this query, there are two ways to do it:
Use the above query as a data-source for a second query (i.e. make it a subquery in the from clause of another query
Create a temp table and query on it
Option 1:
select a.*
from (
-- The query with temp variables defined
)
where -- ATTENTION: you need to write the references to the column names of the subquery
Option 2: (my personal favorite)
drop table if exists temp_my_temp_table;
create temporary table temp_my_temp_table
select
#status1 := (case
when user.id < 500 then 'awesome'
else 'lame'
end) as `status`,
(case
when #status1 = 'awesome' then 'You rock'
else 'You stink'
end) as message
from
user;
-- Add all appropriate indexes to this newly created table:
-- alter table temp_my_temp_table
-- add index idx_status(`status`),
-- add index idx_mess(message);
-- Make your queries on this new temp table
select * from temp_my_temp_table
-- where ...
;
Things you must know about a temp table:
They are created on RAM (by default, and only if the table is not too big)
They are only visible to the connection that created it
They are eliminated once the connection that created it is closed (or terminated in any way)
You can't use it more than once in a FROM clause. Other than that, you can use it as any other table in your database
Another update
Just by chance I came across this question and its answer. If you want to use the result of your column (calculated with temp variables) as a condition, MySQL allows this:
select
#status1 := (case
when user.id < 500 then 'awesome'
else 'lame'
end) as `status`,
(case
when #status1 = 'awesome' then 'You rock'
else 'You stink'
end) as message
from
user
having
`status` = 'awesome';
Instead of using where use having, and refer not to the temp variable, but to the alias of the column.
I have this table :
table(fied1 int,field2 int,field3 varchar(40));
I would like to obtion without a stored procedure something like:
declare int nr default 0;
select coalesce(max(field1),0) into nr from table where field2=? and field3=?;
if(nr = 0) then
select coalesce(max(field1),0)+1 into nr from table;
end if;
i want the value of nr from single select.
pls help !!!
Only use the following query to get one plus to last inserted value in field1 column if no match found as per where clause else it returns the max value stored in field1:
This query is handling the case if there are no records in table.
the filter crieteria "and field1<>0" in following statement is required if field1 can have value 0 also otherwise remove this filter (and field1<>0) from following query
Select coalesce(
max(field1),
(select coalesce(max(field1),0)+1 from table)
)
from table where field2=? and field3=? and field1<>0;
I think this captures your requirements:
SELECT
CASE
WHEN (max(field1) IS NULL OR max(field1) = 0) AND field2=? AND field3=? THEN (max(field1)+1)
ELSE max(field1)
END AS `field1_max`
FROM table
I am trying to use an IF statement in a MySQL select query.
I am getting an error after the AND statement where the first IF.
SELECT J.JOB_ID,E.COMPANY_NAME,J.JOB_DESC,JT.JOBTYPE_NAME,J.COMPENSATION,ST.STATE_NAME,MC.METRO_CITY_NAME,I.INDUSTRY_NAME,
J.JOB_CONTACT_PERSON,J.DT_INSRT,J.JOB_TITLE,J.JOB_EXP_DATE,J.SKILLS
FROM JOBS J
JOIN EMPLOYER E ON J.COMPANY_ID=E.COMPANY_ID
JOIN LOOKUP_JOBTYPE JT ON J.JOB_TYPE=JT.JOBTYPE_ID
JOIN LOOKUP_STATE ST ON J.STATE_ID=ST.STATE_ID
JOIN JOBS_LOCATION JL ON J.JOB_ID=JL.JOB_ID
JOIN LOOKUP_METRO_CITY MC ON JL.METRO_CITY_ID=MC.METRO_CITY_ID
JOIN LOOKUP_INDUSTRY I ON J.INDUSTRY_ID=I.INDUSTRY_ID
JOIN JOBS_QUALIFICATION JQ ON J.JOB_ID=JQ.JOB_ID
JOIN LOOKUP_DEGREE_QUALIFICATION LDQ ON LDQ.QUALIFICATION_ID = JQ.QUALIFICATION_ID
WHERE J.ACTIVE='Y' AND J.DT_INSRT > COALESCE(pEmailSntDt,DATE_SUB(SYSDATE(),INTERVAL 4 DAY))
AND
IF(JQ.COURSE_ID=0)
THEN
IF(JQ.DEGREE_ID=0)
THEN J.SKILLS LIKE CONCAT('%', pSkills,'%')
ELSE
JQ.DEGREE_ID=pDegreeId OR J.SKILLS LIKE CONCAT('%', pSkills,'%')
END IF
ELSE
JQ.COURSE_ID=pCourseId OR IF(JQ.DEGREE_ID=0)
THEN
J.SKILLS LIKE CONCAT('%', pSkills,'%')
ELSE
JQ.DEGREE_ID=pDegreeId OR J.SKILLS LIKE CONCAT('%', pSkills,'%')
END IF
END IF
GROUP BY J.JOB_ID ORDER BY J.DT_INSRT DESC;
Why doesn't this work and what is the proper way to do an IF statement in a MySQL query?
The IF/THEN/ELSE construct you are using is only valid in stored procedures and functions. Your query will need to be restructured because you can't use the IF() function to control the flow of the WHERE clause like this.
The IF() function that can be used in queries is primarily meant to be used in the SELECT portion of the query for selecting different data based on certain conditions, not so much to be used in the WHERE portion of the query:
SELECT IF(JQ.COURSE_ID=0, 'Some Result If True', 'Some Result If False'), OTHER_COLUMNS
FROM ...
WHERE ...
How to use an IF statement in the MySQL "select list":
select if (1>2, 2, 3); //returns 3
select if(1<2,'yes','no'); //returns yes
SELECT IF(STRCMP('test','test1'),'no','yes'); //returns no
How to use an IF statement in the MySQL where clause search condition list:
create table penguins (id int primary key auto_increment, name varchar(100))
insert into penguins (name) values ('rico')
insert into penguins (name) values ('kowalski')
insert into penguins (name) values ('skipper')
select * from penguins where 3 = id
-->3 skipper
select * from penguins where (if (true, 2, 3)) = id
-->2 kowalski
How to use an IF statement in the MySQL "having clause search conditions":
select * from penguins
where 1=1
having (if (true, 2, 3)) = id
-->1 rico
Use an IF statement with a column used in the select list to make a decision:
select (if (id = 2, -1, 1)) item
from penguins
where 1=1
--> 1
--> -1
--> 1
If statements embedded in SQL queries is a bad "code smell". Bad code has high "WTF's per minute" during code review. This is one of those things. If I see this in production with your name on it, I'm going to automatically not like you.
try this code worked for me
SELECT user_display_image AS user_image,
user_display_name AS user_name,
invitee_phone,
(CASE WHEN invitee_status = 1 THEN "attending"
WHEN invitee_status = 2 THEN "unsure"
WHEN invitee_status = 3 THEN "declined"
WHEN invitee_status = 0 THEN "notreviwed"
END) AS invitee_status
FROM your_table
Here are two statements that I'd like to work, but which return error messages:
IF EXISTS (SELECT * FROM gdata_calendars WHERE `group` = ? AND id = ?) SELECT 1 ELSE SELECT 0
and
IF ((SELECT COUNT(*) FROM gdata_calendars WHERE `group` = ? AND id = ?) > 0) SELECT 1 ELSE SELECT 0;
The question marks are there because I use parametrized, prepared, statements with PHP's PDO. However, I have also tried executing this with data manually, and it really does not work.
While I'd like to know why each of them doesn't work, I would prefer to use the first query if it can be made to work.
You cannot use IF control block OUTSIDE of functions. So that affects both of your queries.
Turn the EXISTS clause into a subquery instead within an IF function
SELECT IF( EXISTS(
SELECT *
FROM gdata_calendars
WHERE `group` = ? AND id = ?), 1, 0)
In fact, booleans are returned as 1 or 0
SELECT EXISTS(
SELECT *
FROM gdata_calendars
WHERE `group` = ? AND id = ?)
I found the example RichardTheKiwi quite informative.
Just to offer another approach if you're looking for something like IF EXISTS (SELECT 1 ..) THEN ...
-- what I might write in MSSQL
IF EXISTS (SELECT 1 FROM Table WHERE FieldValue='')
BEGIN
SELECT TableID FROM Table WHERE FieldValue=''
END
ELSE
BEGIN
INSERT INTO TABLE(FieldValue) VALUES('')
SELECT SCOPE_IDENTITY() AS TableID
END
-- rewritten for MySQL
IF (SELECT 1 = 1 FROM Table WHERE FieldValue='') THEN
BEGIN
SELECT TableID FROM Table WHERE FieldValue='';
END;
ELSE
BEGIN
INSERT INTO Table (FieldValue) VALUES('');
SELECT LAST_INSERT_ID() AS TableID;
END;
END IF;
The accepted answer works well and one can also just use the
If Exists (...) Then ... End If;
syntax in Mysql procedures (if acceptable for circumstance) and it will behave as desired/expected. Here's a link to a more thorough source/description: https://dba.stackexchange.com/questions/99120/if-exists-then-update-else-insert
One problem with the solution by #SnowyR is that it does not really behave like "If Exists" in that the (Select 1 = 1 ...) subquery could return more than one row in some circumstances and so it gives an error. I don't have permissions to respond to that answer directly so I thought I'd mention it here in case it saves someone else the trouble I experienced and so others might know that it is not an equivalent solution to MSSQLServer "if exists"!
If your table has an auto-incrementing primary key, you can use REPLACE INTO ... VALUES
SELECT #id := id FROM tableName WHERE fieldName='criteria value' LIMIT 1;
REPLACE INTO tableName(id, fieldName, col1, col2)
VALUES (#id, 'criteria value', 'value1', 'value2')
If the select statement returns NULL, then a new row is inserted.
Otherwise, if a row is found, it will update the row with key #id.
SELECT IF((
SELECT count(*) FROM gdata_calendars
WHERE `group` = ? AND id = ?)
,1,0);
For Detail explanation you can visit here
Hello im having a hard time with this stored procedure. im getting the error:
Result consisted of more than one row.
here is my stored procedure:
DELIMITER $$
DROP PROCEDURE IF EXISTS `dss`.`COSTRET` $$
CREATE DEFINER=`dwadmin`#`192.168.%.%` PROCEDURE `COSTRET`( TDATE DATE)
BEGIN
DECLARE done INT DEFAULT 0;
DECLARE ls_id VARCHAR(8);
DECLARE ld_cost DECIMAL(10,4);
DECLARE ld_retail DECIMAL(10,4);
DECLARE cur1 CURSOR FOR SELECT DISTINCT `id` FROM `prod_performance` WHERE `psc_week` = TDATE;
DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET done = 1;
-- Get the Cost
CREATE TEMPORARY TABLE IF NOT EXISTS `prod_itemcost`
SELECT DISTINCTROW `itemcode` ID, `mlist` COST
FROM (SELECT `itemcode`, `pceffdate`, `mlist`
FROM `purchcost` a
where `pceffdate` = (SELECT MAX(z.`pceffdate`) FROM `purchcost` z WHERE z.`itemcode` = a.`itemcode`
AND z.`pceffdate` <= TDATE)) tb
ORDER BY `itemcode`;
OPEN cur1;
REPEAT
FETCH cur1 INTO ls_id;
IF NOT done THEN
SELECT DISTINCTROW `cost` INTO ld_cost FROM `prod_itemcost` WHERE id = ls_id;
UPDATE LOW_PRIORITY `prod_performance` SET `current_cost` = ld_cost WHERE `psc_week` = TDATE and `id` = ls_id;
END IF;
UNTIL done END REPEAT;
CLOSE cur1;
-- Destroy Temporary Tables
DROP TEMPORARY TABLES IF EXISTS `prod_itemcost`;
END $$
DELIMITER ;
Any solutions and recommendations are much appreciated!
I'd say the problem is here :
SELECT DISTINCTROW `cost` INTO ld_cost FROM `prod_itemcost` WHERE id = ls_id;
and caused by this returning more than one row.
How you solve it depends on your requirements. Does the existence of multiple rows imply the database is in need of some cleaning, for example? Or should you be taking the first value of 'cost', or perhaps the sum of all 'cost' for id = ls_id?
Edit :
Your INTO clause is attempting to write multiple rows to a single variable. Looking at your SQL, I'd say the underlying problem is that your initial query to pull back just the latest cost for each ID is being hamstrung by duplicates of pceffdate. If this is the case, this SQL :
SELECT DISTINCTROW `itemcode` ID, `mlist` COST
FROM (SELECT `itemcode`, `pceffdate`, `mlist`
FROM `purchcost` a
where `pceffdate` = (SELECT MAX(z.`pceffdate`) FROM `purchcost` z WHERE z.`itemcode` = a.`itemcode`
AND z.`pceffdate` <= TDATE)) tb
will return more rows than just this :
SELECT DISTINCTROW `itemcode` ID
FROM (SELECT `itemcode`, `pceffdate`, `mlist`
FROM `purchcost` a
where `pceffdate` = (SELECT MAX(z.`pceffdate`) FROM `purchcost` z WHERE z.`itemcode` = a.`itemcode`
AND z.`pceffdate` <= TDATE)) tb
This line
SELECT MAX(z.`pceffdate`) FROM `purchcost` z WHERE z.`itemcode` = a.`itemcode`
AND z.`pceffdate` <= TDATE
has got to be the problem. It must be returning more than 1 row. So, the DBMS is trying to set multiple values to the same thing, which of course it cannot do.
Do you need something else in your WHERE clause there?
The problem is that
SELECT DISTINCTROW `itemcode` ID, `mlist` COST
could store multiple costs against each ID, and so
SELECT DISTINCTROW `cost` INTO ld_cost FROM `prod_itemcost` WHERE id = ls_id;
could return multiple rows for each id.
For example, if purchcost contained the following:
itemcode mlist pceffdate
1 10.99 10-apr-2009
1 11.99 10-apr-2009
1 9.99 09-apr-2009
Then temporary table prod_itemcost would contain:
itemcode mlist
1 10.99
1 11.99
These both being values that were in effect on the most recent pceffdate for that itemcode.
This would then cause a problem with selecting mlist into ld_cost for itemcode 1 because there are two matching values, and the scalar ld_cost can only hold one.
You really need to look at the data in purchcost. If it is possible for 1 item to have more than one entry with different mlist values for the same date/datetime, then you need to decide how that should be handled. Perhaps take the highest value, or the lowest value, or any value. Or perhaps this is an error in the data.
There is another possibility, that is your parameter "TDATE" same as table field name in uppercase or lowercase or mixed. such as 'tdate', 'tDate', 'TDATE'.
so you should check that. I hit this before.
You are inserting an array in a variable instead of a single value that's why its problem occurs.
Like:
DECLARE name varchar;
select f_name into name from student;
here name will accept only single name instead of multiple name;