Alright, so I have a table that has a count field that is between 0 and 100. Up to six of these fields are tied to a single id. I need to run an update that will decrease each of these rows by a different random number between 1 and 3.
I know I can get my random value with:
CAST(RAND() * 3 AS UNSIGNED)
And I know I can get my update to work with:
UPDATE Info SET Info.count = CASE WHEN Info.count < 2 THEN 0 ELSE Info.count - 2 END WHERE Info.id = $iid AND Info.type = 'Active';
(This just makes sure I will never dip below 0)
But I cannot combine them for the obvious reason that my random number will be different when evaluated then when it's set...
UPDATE Info SET Info.count = CASE WHEN Info.count < CAST(RAND() * 3 AS UNSIGNED) THEN 0 ELSE Info.count - CAST(RAND() * 3 AS UNSIGNED) END WHERE Info.id = $iid AND Info.type = 'Active';
Now I don't want to save just 1 variable, because I may need up to 6 different numbers...is there a way to do what I want to do in a single query? I know how I can do it in multiple, but I really shouldn't be running up to 6 queries every time I need to update one of these blocks...
The table structure I'm working off of is:
CREATE TABLE `Info` (
`id` int(40) DEFAULT NULL,
`count` int(11) DEFAULT NULL,
`type` varchar(40) DEFAULT NULL,
`AUTOINC` int(11) unsigned NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`AUTOINC`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8;
The AUTOINC field at the moment is just so I can easily verify what's going on during testing.
Thanks!
You're probably best off writing a procedure to do this. So you could write something to the extent of (pseudo code)
create procedure update()
begin
declare id, count, sub int;
declare c cursor for select id, count floor(1+rand()*3) from info
where type='Active';
open c;
loop
fetch c into id, count, sub;
update info set case count - sub < 0 then 0 else count - sub end
where id = id;
end loop;
close c;
end
//
Or you can change the procedure to accept an ID like I had it before and simply use one select and one update statement.
Related
I am creating a procedure that updates any invoice with unpaid status for more than 30 days to 'OVERDUE'. However with my current code whenever I am calling this procedure even the invoice which does not have UNPAID status gets its status updated to OVERDUE.
CREATE procedure sync_invoice()
begin
declare dDate date;
declare stat varchar(20);
declare d_finished int default 0;
declare d_array cursor for
select DATEISSUED, STATUS from invoice;
declare continue handler for not found set d_finished = 1;
open d_array;
repeat
fetch d_array into dDate, stat;
if (datediff(current_date(), dDate)> 30 )then
update invoice
set STATUS = 'OVERDUE'
where stat = 'UNPAID';
end if;
until d_finished
end repeat;
close d_array;
-- code
end
//
here is the invoice table
CREATE TABLE IF NOT EXISTS `invoice` (
`INVOICENO` INT(11) NOT NULL AUTO_INCREMENT,
`CAMPAIGN_NO` INT(11) NOT NULL,
`DATEISSUED` DATE NULL DEFAULT NULL,
`DATEPAID` DATE NULL DEFAULT NULL,
`BALANCEOWING` INT(11) NULL DEFAULT NULL,
`STATUS` VARCHAR(20) NULL DEFAULT NULL,
PRIMARY KEY (`INVOICENO`, `CAMPAIGN_NO`),
INDEX `FK_INVOICE_SENDS2_CAMPAIGN_idx` (`CAMPAIGN_NO` ASC),
CONSTRAINT `FK_INVOICE_SENDS2_CAMPAIGN`
FOREIGN KEY (`CAMPAIGN_NO`)
REFERENCES `campaign` (`CAMPAIGN_NO`)
ON DELETE RESTRICT
ON UPDATE RESTRICT)
AUTO_INCREMENT = 6;
Ok so there are a few wrong things here:
CREATE procedure sync_invoice()
begin
declare dDate date;
declare stat varchar(20);
declare d_finished int default 0;
declare d_array cursor for
select DATEISSUED, STATUS from invoice;
declare continue handler for not found set d_finished = 1;
open d_array;
repeat
-- The loop will be executed for each entry into invoice
fetch d_array into dDate, stat;
-- For each, if it's old enough, regardless of the status...
if (datediff(current_date(), dDate)> 30 )then
-- This SQL request, which is called over the whole invoice table is executed
update invoice
set STATUS = 'OVERDUE' -- Effectively setting the status to overdue
where stat = 'UNPAID'; -- for each entry, so far that the one inspected is UNPAID
end if;
until d_finished
end repeat;
close d_array;
-- code
end
So basically, with this code, you'll always set every invoice to OVERDUE so long that there is a single, 30+ days old UNPAID invoice in the table.
Some way around this include replacing the whole content of the procedure by the single appropriate UPDATE call:
Update invoice Set STATUS = 'OVERDUE' Where datediff(current_date(), DATEISSUED) > 30 And STATUS = 'UNPAID';
Edit: To clarify, you could 'fix' the whole thing by replacing 'stat' at line where stat = 'UNPAID'; by 'STATUS', but you would still be executing way too many instructions without any reason to, effectively iterating through your whole invoice table as many time as you have 30+ days old invoices.
But in practice, SQL is a quite powerful language in which you might not need to loop yourself for tasks working with a single entry in a table. Statements such as UPDATE ... WHERE ... do it for you. c:
Loops and cursor, then, become useful when you have to do process that need to consider multiple entry at once.
I tried to write a SQL-function that generates an unused unique ID in a range between 1000000 and 4294967295. I need numeric values, so UUID() alike is not a solution. It doesn't sound that difficult, but for some reason, the code below does not work when called within an INSERT-statement on a table as value for the primary key (not auto_increment, of course). The statement is like INSERT INTO table (id, content) VALUES ((SELECT getRandomID(0,0)), 'blabla bla');
(Since default values are not allowed in such functions, I shortly submit 0 for each argument and set it in the function to the desired value.)
Called once and separated from INSERT or Python-code, everything is fine. Called several times, something weird happens and not only the whole process but also the server might hang within REPEAT. The process is then not even possible to kill/restart; I have to reboot the machine -.-
It also seems to only have some random values ready for me, since the same values appear again and again after some calls, allthough I actually thought that the internal rand() would be a sufficient start/seed for the outer rand().
Called from Python, the loop starts to hang after some rounds although the very first one in my tests always produces a useful, new ID and therefore should quit after the first round. Wyh? Well, the table is empty...so SELECT COUNT(*)... returns 0 which actually is the signal for leaving the loop...but it doesn't.
Any ideas?
I'm running MariaDB 10.something on SLES 12.2. Here is the exported source code:
DELIMITER $$
CREATE DEFINER=`root`#`localhost` FUNCTION `getRandomID`(`rangeStart` BIGINT UNSIGNED, `rangeEnd` BIGINT UNSIGNED) RETURNS bigint(20) unsigned
READS SQL DATA
BEGIN
DECLARE rnd BIGINT unsigned;
DECLARE i BIGINT unsigned;
IF rangeStart is null OR rangeStart < 1 THEN
SET rangeStart = 1000000;
END IF;
IF rangeEnd is null OR rangeEnd < 1 THEN
SET rangeEnd = 4294967295;
END IF;
SET i = 0;
r: REPEAT
SET rnd = FLOOR(rangeStart + RAND(RAND(FLOOR(1 + rand() * 1000000000))*10) * (rangeEnd - rangeStart));
SELECT COUNT(*) INTO i FROM `table` WHERE `id` = rnd;
UNTIL i = 0 END REPEAT r;
RETURN rnd;
END$$
DELIMITER ;
A slight improvement:
SELECT COUNT(*) INTO i FROM `table` WHERE `id` = rnd;
UNTIL i = 0 END REPEAT r;
-->
UNTIL NOT EXISTS( SELECT 1 FROM `table` WHERE id = rnd ) REPEAT r;
Don't pass any argument to RAND -- that is for establishing a repeatable sequence of random numbers.
mysql> SELECT RAND(123), RAND(123), RAND(), RAND()\G
*************************** 1. row ***************************
RAND(123): 0.9277428611440052
RAND(123): 0.9277428611440052
RAND(): 0.5645420109522921
RAND(): 0.12561983719991504
1 row in set (0.00 sec)
So simplify to
SET rnd = FLOOR(rangeStart + RAND() * (rangeEnd - rangeStart));
If you want to include rangeEnd in the possible outputs, add 1:
SET rnd = FLOOR(rangeStart + RAND() * (rangeEnd - rangeStart + 1));
Can anyone help me how to check duplicate values from multiple comma separated value. I have a customer table and in that one can insert multiple comma separated contact number and I want to check duplicate values from last five digits.For reference check screenshot attached and the required output is
contact_no. count
97359506775 -- 2
390558073039-- 1
904462511251-- 1
I would advise you to redesign your database schema, if possible. Your current database violates First Normal Form since your attribute values are not indivisible.
Create a table where id together with a single phone number constitutes a key, this constraint enforces that no duplicates occur.
I don't remember much but I will try to put the idea (it's something which I had used a long time ago):
Create a table value function which will take the id and phone number as input and then generate a table with id and phone numbers and return it.
Use this function in query passing id and phone number. The query is such that for each id you get as many rows as the phone numbers. CROSS APPLY/OUTER APPLY needs to be used.
Then you can check for the duplicates.
The function would be something like this:
CREATE FUNCTION udf_PhoneNumbers
(
#Id INT
,#Phone VARCHAR(300)
) RETURNS #PhonesTable TABLE(Id INT, Phone VARCHAR(50))
BEGIN
DECLARE #CommaIndex INT
DECLARE #CurrentPosition INT
DECLARE #StringLength INT
DECLARE #PhoneNumber VARCHAR(50)
SELECT #StringLength = LEN(#Phone)
SELECT #CommaIndex = -1
SELECT #CurrentPosition = 1
--index is 1 based
WHILE #CommaIndex < #StringLength AND #CommaIndex <> 0
BEGIN
SELECT #CommaIndex = CHARINDEX(',', #Phone, #CurrentPosition)
IF #CommaIndex <> 0
SELECT #PhoneNumber = SUBSTRING(#Phone, #CurrentPosition, #CommaIndex - #CurrentPosition)
ELSE
SELECT #PhoneNumber = SUBSTRING(#Phone, #CurrentPosition, #StringLength - #CurrentPosition + 1)
SELECT #CurrentPosition = #CommaIndex + 1
INSERT INTO #UsersTable VALUES(#Id, #PhoneNumber)
END
RETURN
END
Then run CROSS APPLY query:
SELECT
U.*
,UD.*
FROM yourtable U CROSS APPLY udf_PhoneNumbers(Userid, Phone) UD
This will give you the table on which you can run query to find duplicate.
I have a database table like this sample:
ID THINGS HAS_DUPLICATES
1 AAA, BBB, AAA NULL
2 CCC, DDD NULL
I am trying to write a stored procedure to flag duplicate values in THINGS field.
After calling the procedure the table will become like this:
ID THINGS HAS_DUPLICATES
1 AAA, BBB, AAA YES
2 CCC, DDD NO
Please be informed that I am trying to resolve it using only SQL and without normalizing my database. I am also aware of other approaches like writing PHP code.
Schema:
DROP TABLE IF EXISTS evilThings; -- orig table with dupes
CREATE TABLE evilThings
( ID INT AUTO_INCREMENT PRIMARY KEY,
THINGS TEXT NOT NULL,
HAS_DUPLICATES INT NULL
);
INSERT evilThings(ID,THINGS) VALUES
(1,"'AAA, BBB, AAA'"),
(2,"'CCC, DDD'");
CREATE TABLE notEvilAssocTable
( ai INT AUTO_INCREMENT PRIMARY KEY, -- no shuffle on inserts
ID INT NOT NULL,
THING VARCHAR(100) NOT NULL,
UNIQUE KEY `unqK_id_thing` (ID,THING) -- no dupes, this is honorable
);
Stored Proc:
DROP PROCEDURE IF EXISTS splitEm;
DELIMITER $$
CREATE PROCEDURE splitEm()
BEGIN
DECLARE lv_ID,pos1,pos2,comma_pos INT;
DECLARE lv_THINGS TEXT;
DECLARE particle VARCHAR(100);
DECLARE strs_done INT DEFAULT FALSE; -- string search done
DECLARE done INT DEFAULT FALSE; -- cursor done
DECLARE cur111 CURSOR FOR SELECT ID,THINGS FROM evilThings ORDER BY ID;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
-- Please note in the above, CURSOR stuff MUST come LAST else "Error 1337: Variable or condition decl aft curs"
-- -------------------------------------------------------------------------------------------------------------------
TRUNCATE TABLE notEvilAssocTable;
OPEN cur111;
read_loop: LOOP
SET strs_done=FALSE;
FETCH cur111 INTO lv_ID,lv_THINGS;
IF done THEN
LEAVE read_loop;
END IF;
SET pos1=1,comma_pos=0;
WHILE !strs_done DO
SET pos2=LOCATE(',', lv_THINGS, comma_pos+1);
IF pos2=0 THEN
SET pos2=LOCATE("'", lv_THINGS, comma_pos+1);
IF pos2!=0 THEN
SET particle=SUBSTRING(lv_THINGS,comma_pos+1,pos2-comma_pos-1);
SET particle=REPLACE(particle,"'","");
SET particle=TRIM(particle);
INSERT IGNORE notEvilAssocTable (ID,THING) VALUES (lv_ID,particle);
END IF;
SET strs_done=1;
ELSE
SET particle=SUBSTRING(lv_THINGS,comma_pos+1,pos2-comma_pos-1);
SET particle=REPLACE(particle,"'","");
SET particle=TRIM(particle);
INSERT IGNORE notEvilAssocTable (ID,THING) VALUES (lv_ID,particle);
SET comma_pos=pos2;
END IF;
END WHILE;
END LOOP;
CLOSE cur111; -- close the cursor
END$$
DELIMITER ;
Test:
call splitEm();
See results of split:
select * from notEvilAssocTable;
Note that position 3, the InnoDB gap (from INSERT IGNORE). It is simply the innodb gap anomaly, an expected side effect like so many of InnoDB. In this case driven by the IGNORE part that creates a gap. No problem though. It forbids duplicates in our new table for split outs. It is common. It is there to protect you.
If you did not mean to have the single quote at the beginning and end of the string in the db, then change the routine accordingly.
Here is the answer to my question, assuming the data in THINGS field are separated by a bar '|'. Our original table will be myTABLE:
ID THINGS THINGSCount THINGSCountUnique HAS_DUPLICATES
1 AAA|BBB|AAA NULL NULL NULL
2 CCC|DDD NULL NULL NULL
Step 1. Check the maximum number of values separated by a bar '|' in THINGS field:
SELECT ROUND((CHAR_LENGTH(THINGS) - CHAR_LENGTH(REPLACE(THINGS,'|',''))) / CHAR_LENGTH('|')) + 1 FROM myTABLE;
Step 2. Assuming the answer from step 1 was 7, now use the following SQL to split the data in THINGS field into rows, there are many other approaches which you can Google to do the split:
CREATE TABLE myTABLE_temp
SELECT ID, SUBSTRING_INDEX(SUBSTRING_INDEX(myTABLE.THINGS, '|', n.n), '|', -1) THINGS
FROM myTABLE JOIN
( SELECT n FROM
( SELECT 1 AS N UNION ALL SELECT 2 UNION ALL SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL SELECT 6 UNION ALL SELECT 7 ) a ) n
ON CHAR_LENGTH(THINGS) - CHAR_LENGTH(REPLACE(THINGS, '|', '')) >= n - 1
ORDER BY ID;
Our myTABLE_temp table will be something like:
ID THINGS
1 AAA
1 BBB
1 AAA
2 CCC
2 DDD
Step 3. Here we create two new tables to hold COUNT(THINGS) and COUNT(DISTINCT THINGS) as following:
# THINGSCount
CREATE TABLE myTABLE_temp_2
SELECT ID, COUNT(THINGS) AS THINGSCount FROM myTABLE_temp GROUP BY ID;
# Remember to ADD INDEX to ID field
UPDATE myTABLE A INNER JOIN myTABLE_temp_2 B ON(A.ID = B.ID) SET A.THINGSCount = B.THINGSCount;
# THINGSCountUnique
CREATE TABLE myTABLE_temp_3
SELECT ID, COUNT(THINGS) AS THINGSCountUnique FROM myTABLE_temp GROUP BY ID;
# Remember to ADD INDEX to ID field
UPDATE myTABLE A INNER JOIN myTABLE_temp_3 B ON(A.ID = B.ID) SET A.THINGSCountUnique = B.THINGSCountUnique;
Final Step: Flag duplicate values:
UPDATE myTABLE SET HAS_DUPLICATES = IF(THINGSCount>THINGSCountUnique, 'DUPLICATES', 'NO');
I have a stored procedure that returns a common query, I need to call it in several functions but some functions may call it through Period Id or others through Header Id, so far I would like to know how can I determine what param to use in order to retrive data properly, I have something like this implemented.
CREATE PROCEDURE dbo.GetTFDRecordInfo
#PeriodId int = null,
#HeaderId int = null
AS
BEGIN
SELECT
-- I have a lot more fields and joins here, that's why I need to get the statement in a single call through either period id or header id
*
From NT_CSRTNVPeriodInfo t
-- how can I make possible something like shown above, can I use a "Case When"?
Where (
/*
if #PeriodId is null
Where t.HeaderId = #HeaderId
if #HeaderId is null
Where t.PeriodId = #PeriodId
*/
)
END
GO
-- swtich between params
Exec NT_CSRTNVPeriodInfo null, 2654
Exec NT_CSRTNVPeriodInfo 196, null
This is the answer:
CREATE PROCEDURE dbo.GetTFDRecordInfo
#PeriodId int = null,
#HeaderId int = null
AS
BEGIN
SELECT
-- I have a lot more fields and joins here, that's why I need to get the statement in a single call through either period id or header id
*
From NT_CSRTNVPeriodInfo t
-- how can I make possible something like shown above, can I use a "Case When"?
Where ((#PeriodId IS NULL) or (t.PeriodId = #PeriodId))
And ((#HeaderId IS NULL) or (t.HeaderId = #HeaderId))
END
GO
You have to use conditional OR to check NULLs, if param is set, the second condition is checked, if not, the procedure will consider always true the statement and go to the next.