I have a routine. But it' s too slow. How can I improve the query?
My records: http://www.sqlfiddle.com/#!9/14cceb/1/0
My query:
CREATE DEFINER = 'root'#'localhost'
PROCEDURE example.ssa()
BEGIN
drop table if exists gps_table;
drop table if exists exam_datas;
CREATE TEMPORARY TABLE gps_table(ID int PRIMARY KEY AUTO_INCREMENT,timei
int,
trun_date_time datetime, tadd_meter int, tin_here int null);
insert into gps_table(timei,trun_date_time,tadd_meter,tin_here) select
imei, run_date_time, add_meter, in_here from example_table;
CREATE TEMPORARY TABLE exam_datas(ID int PRIMARY KEY AUTO_INCREMENT,vimei
int, vbas_run_date_time datetime, vbit_run_date_time datetime, vdifff int);
select tin_here from gps_table limit 1 into #onceki_durum;
select count(id) from gps_table into #kayit_sayisi;
set #i = 1;
set #min_mes = 0;
set #max_mes = 0;
set #frst_id = 0;
set #imei = 0;
set #run_date_time = '0000-00-00 00:00:00';
set #run_date_time2 = '0000-00-00 00:00:00';
myloop: WHILE (#i <= #kayit_sayisi) DO
select tin_here from gps_table where id = #i into #in_here_true;
if (#in_here_true = 1) then
select id,trun_date_time, tadd_meter from gps_table where id = #i into #frst_id,#run_date_time2, #min_mes;
select id from gps_table where id > #frst_id and tin_here =0 order by id asc limit 1 INTO #id;
SET #id = #id-1;
select id, timei, trun_date_time, tadd_meter from gps_table
where id = #id and tin_here =1 limit 1 into #i, #imei, #run_date_time, #max_mes;
if(#i-#frst_id>3) then
set #i:=#i+1;
insert into exam_datas(vimei,vbas_run_date_time,vbit_run_date_time,vdifff) Values (#imei, #run_date_time2, #run_date_time, #max_mes-#min_mes);
SELECT * FROM exam_datas;
SET #asd =1;
elseif 1=1 then
set #i:=#i+1;
End if;
ELSEIF 1=1
THEN SET #i:=#i+1;
End if;
IF (#i = #kayit_sayisi)
THEN set #tamam =1; LEAVE myloop;
END IF;
END WHILE myloop;
select DISTINCT * from exam_datas;
drop table if exists exam_datas;
drop table if exists gps_table;
END
I need: id= 6 first true and id= 11 last_true
firs_trure - last_true = 304-290= 14
id=14 first true and id=18 last_true
firs_true - last_true = 332-324= 8
This routine is too slow.
MySql version is 5.7 and There are 2 milions record in the table.
UPDATE:
Query is here. HERE
Thank you #LukStorms
It's possible to get such results in 1 query.
Thus avoiding a WHILE loop over records.
This example works without using window functions. Just using variables inside the query to calculate a rank. Which is then used to get the minimums and maximums of the groups.
select
imei,
min(run_date_time) as start_dt,
max(run_date_time) as stop_dt,
max(add_meter) - min(add_meter) as diff
from
(
select imei, id, run_date_time, add_meter, in_here,
case
when #prev_imei = imei and #prev_ih = in_here then #rnk
when #rnk := #rnk + 1 then #rnk
end as rnk,
#prev_imei := imei as prev_imei,
#prev_ih := in_here as prev_ih
from example_table t
cross join (select #rnk := 0, #prev_ih := null, #prev_imei := null) vars
order by imei, id, run_date_time
) q
where in_here = 1
group by imei, rnk
having count(*) > 4
order by imei, min(id);
In the procedure such query can be used to fill that final temporary table.
A test on db<>fiddle here
I am new to StackOverflow and have got stuck with a query to print prime numbers from 2 to 1000.
I have used the below query need input if this is the most efficient way to code it.
WITH NUM AS (
SELECT LEVEL N
FROM DUAL CONNECT BY LEVEL <= 1000
)
SELECT LISTAGG(B.N,'-') WITHIN GROUP(ORDER BY B.N) AS PRIMES
FROM (
SELECT N,
CASE WHEN EXISTS (
SELECT NULL
FROM NUM N_INNER
WHERE N_INNER .N > 1
AND N_INNER.N < NUM.N
AND MOD(NUM.N, N_INNER.N)=0
) THEN
'NO PRIME'
ELSE
'PRIME'
END IS_PRIME
FROM NUM
) B
WHERE B.IS_PRIME='PRIME'
AND B.N!=1;
I know this question has been asked multiple times and I am requesting better solution if any. More over need input on how this works with MySQL/MS SQL/PostgreSQL.
Any help will make my understanding better.
In PostgreSQL probably the most fastest query that prints prime numbers up to 1000 is:
SELECT regexp_split_to_table('2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293,307,311,313,317,331,337,347,349,353,359,367,373,379,383,389,397,401,409,419,421,431,433,439,443,449,457,461,463,467,479,487,491,499,503,509,521,523,541,547,557,563,569,571,577,587,593,599,601,607,613,617,619,631,641,643,647,653,659,661,673,677,683,691,701,709,719,727,733,739,743,751,757,761,769,773,787,797,809,811,821,823,827,829,839,853,857,859,863,877,881,883,887,907,911,919,929,937,941,947,953,967,971,977,983,991,997',E',')::int
AS x
;
It took only 16 ms on my computer.
Note: a list of prime numbers was copied from https://en.wikipedia.org/wiki/Prime_number
and pasted into this long string
If you prefer SQL, then this works
WITH x AS (
SELECT * FROM generate_series( 2, 1000 ) x
)
SELECT x.x
FROM x
WHERE NOT EXISTS (
SELECT 1 FROM x y
WHERE x.x > y.x AND x.x % y.x = 0
)
;
It's two times slower - 31 ms.
Ans an equivalent version for Oracle:
WITH x AS(
SELECT level+1 x
FROM dual
CONNECT BY LEVEL <= 999
)
SELECT x.x
FROM x
WHERE NOT EXISTS (
SELECT 1 FROM x y
WHERE x.x > y.x AND remainder( x.x, y.x) = 0
)
;
The most obvious improvement is that instead of checking from 1 to n you can check from 1 to the square root of n.
A second major optimization would be to use a temporary table to store the results and check them first. This way you can iterate incrementally from 1 to n, and only check the known primes from 1 to square root of n (recursively doing that until you have a list). If you go about things this way you would probably want to set up the prime detection in a function and then do the same with your number series generator.
That second one though means extending SQL and so I don't know if that fits your requirements.
For postgresql I would use generate_series go generate the list of numbers. I would then create functions which would then either store the list of primes in a temporary table or pass them back in and out in an ordered array and then couple them like that
MariaDB (with sequence plugin)
Similar to kordirkos algorithm:
select 2 as p union all
select n.seq
from seq_3_to_1000_step_2 n
where not exists (
select 1
from seq_3_to_32_step_2 q
where q.seq < n.seq
and n.seq mod q.seq = 0
);
Using LEFT JOIN:
select 2 as p union all
select n.seq
from seq_3_to_1000_step_2 n
left join seq_3_to_32_step_2 q
on q.seq < n.seq
and n.seq mod q.seq = 0
where q.seq is null;
MySQL
There are no sequence generating helpers in MySQL. So the sequence tables have to be created first:
drop temporary table if exists n;
create temporary table if not exists n engine=memory
select t2.c*100 + t1.c*10 + t0.c + 1 as seq from
(select 0 c union all select 1 c union all select 2 c union all select 3 c union all select 4 c union all select 5 c union all select 6 c union all select 7 c union all select 8 c union all select 9 c) t0,
(select 0 c union all select 1 c union all select 2 c union all select 3 c union all select 4 c union all select 5 c union all select 6 c union all select 7 c union all select 8 c union all select 9 c) t1,
(select 0 c union all select 1 c union all select 2 c union all select 3 c union all select 4 c union all select 5 c union all select 6 c union all select 7 c union all select 8 c union all select 9 c) t2
having seq > 2 and seq % 2 != 0;
drop temporary table if exists q;
create temporary table if not exists q engine=memory
select *
from n
where seq <= 32;
alter table q add primary key seq (seq);
Now similar queries can be used:
select 2 as p union all
select n.seq
from n
where not exists (
select 1
from q
where q.seq < n.seq
and n.seq mod q.seq = 0
);
select 2 as p union all
select n.seq
from n
left join q
on q.seq < n.seq
and n.seq mod q.seq = 0
where q.seq is null;
sqlfiddle
Oracle and without inner select in getting part:
with tmp(id)
as (
select level id from dual connect by level <= 100
) select t1.id from tmp t1
JOIN tmp t2
on MOD(t1.id, t2.id) = 0
group by t1.ID
having count(t1.id) = 2
order by t1.ID
;
/* Below is my solution */
/* Step 1: Get all the numbers till 1000 */
with tempa as
(
select level as Num
from dual
connect by level<=1000
),
/* Step 2: Get the Numbers for finding out the factors */
tempb as
(
select a.NUm,b.Num as Num_1
from tempa a , tempa b
where b.Num<=a.Num
),
/*Step 3:If a number has exactly 2 factors, then it is a prime number */
tempc as
(
select Num, sum(case when mod(num,num_1)=0 then 1 end) as Factor_COunt
from tempb
group by Num
)
select listagg(Num,'&') within group (order by Num)
from tempc
where Factor_COunt=2
;
Tested on sqlite3
WITH nums(n) AS
(
SELECT 1
UNION ALL
SELECT n + 1 FROM nums WHERE n < 100
)
SELECT n
FROM (
SELECT n FROM nums
)
WHERE n NOT IN (
SELECT n
FROM nums
JOIN ( SELECT n AS n2 FROM nums )
WHERE n <> 1
AND n2 <> 1
AND n <> n2
AND n2 < n
AND n % n2 = 0
ORDER BY n
)
AND n <> 1
Tested on Vertica 8
WITH seq AS (
SELECT ROW_NUMBER() OVER() AS n
FROM (
SELECT 1
FROM (
SELECT date(0) + INTERVAL '1 second' AS i
UNION ALL
SELECT date(0) + INTERVAL '100 seconds' AS i
) _
TIMESERIES tm AS '1 second' OVER(ORDER BY i)
) _
)
SELECT n
FROM (SELECT n FROM seq) _
WHERE n NOT IN (
SELECT n FROM (
SELECT s1.n AS n, s2.n AS n2
FROM seq AS s1
CROSS JOIN seq AS s2
ORDER BY n, n2
) _
WHERE n <> 1
AND n2 <> 1
AND n <> n2
AND n2 < n
AND n % n2 = 0
)
AND n <> 1
ORDER BY n
This is what worked for me in the SQL server. I tried to reduce the order of my nested loops.
declare #var int
declare #i int
declare #result varchar (max)
set #var = 1
select #result = '2&3&5' --first few obvious prime numbers
while #var < 1000 --the first loop
begin
set #i = 3;
while #i <= #var/2 --the second loop which I attempted to reduce the order
begin
if #var%#i = 0
break;
if #i=#var/2
begin
set #result = #result + '&' + CAST(#var AS VARCHAR)
break;
end
else
set #i = #i + 1
end
set #var = #var + 1;
end
print #result
SELECT LISTAGG(PRIME_NUMBER,'&') WITHIN GROUP (ORDER BY PRIME_NUMBER)
FROM
(
SELECT L PRIME_NUMBER FROM
(
SELECT LEVEL L FROM DUAL CONNECT BY LEVEL <= 1000 ),
(
SELECT LEVEL M FROM DUAL CONNECT BY LEVEL <= 1000
) WHERE M <= L
GROUP BY L
HAVING COUNT(CASE WHEN L/M = TRUNC(L/M) THEN 'Y' END
) = 2
ORDER BY L
);
SELECT GROUP_CONCAT(NUMB SEPARATOR '&')
FROM (
SELECT #num:=#num+1 as NUMB FROM
information_schema.tables t1,
information_schema.tables t2,
(SELECT #num:=1) tmp
) tempNum
WHERE NUMB<=1000 AND NOT EXISTS(
SELECT * FROM (
SELECT #nu:=#nu+1 as NUMA FROM
information_schema.tables t1,
information_schema.tables t2,
(SELECT #nu:=1) tmp1
LIMIT 1000
) tatata
WHERE FLOOR(NUMB/NUMA)=(NUMB/NUMA) AND NUMA<NUMB AND NUMA>1
)
MySQL Code :
DECLARE
#i INT,
#a INT,
#count INT,
#p nvarchar(max)
SET #i = 1
WHILE (#i <= 1000)
BEGIN SET #count = 0
SET #a = 1
WHILE (#a <= #i)
BEGIN IF (#i % #a = 0) SET #count = #count + 1 SET #a = #a + 1
END IF (#count = 2) SET #P = CONCAT(#P,CONCAT(#i,'&')) SET #i = #i + 1
END
PRINT LEFT(#P, LEN(#P) - 1)
The below code works to find prime numbers in SQL
Tested on SampleDB of local server
CREATE procedure sp_PrimeNumber(#number int)
as
begin
declare #i int
declare #j int
declare #isPrime int
set #isPrime=1
set #i=2
set #j=2
while(#i<=#number)
begin
while(#j<=#number)
begin
if((#i<>#j) and (#i%#j=0))
begin
set #isPrime=0
break
end
else
begin
set #j=#j+1
end
end
if(#isPrime=1)
begin
SELECT #i
end
set #isPrime=1
set #i=#i+1
set #j=2
end
end
I have created the stored procedure which has a parameter #number to find the prime numbers up to that given number
In order to get the prime numbers we can execute the below stored procedure
EXECUTE sp_PrimeNumber 100 -- gives prime numbers up to 100
If you are new to stored procedures and want to find the prime numbers in SQL we can use the below code
Tested on master DB
declare #i int
declare #j int
declare #isPrime int
set #isPrime=1
set #i=2
set #j=2
while(#i<=100)
begin
while(#j<=100)
begin
if((#i<>#j) and (#i%#j=0))
begin
set #isPrime=0
break
end
else
begin
set #j=#j+1
end
end
if(#isPrime=1)
begin
SELECT #i
end
set #isPrime=1
set #i=#i+1
set #j=2
end
This code can give the prime numbers between 1 to 100. If we want to find more prime numbers edit the #i and #j arguments in the while loop and execute
Simple query in PostgreSQL:
SELECT serA.el AS prime
FROM generate_series(2, 100) serA(el)
LEFT JOIN generate_series(2, 100) serB(el) ON serA.el >= POWER(serB.el, 2)
AND serA.el % serB.el = 0
WHERE serB.el IS NULL
Enjoy! :)
For SQL Server We can use below CTE
SET NOCOUNT ON
;WITH Prim AS
(
SELECT 2 AS Value
UNION ALL
SELECT t.Value+1 AS VAlue
FROM Prim t
WHERE t.Value < 1000
)SELECT *
FROM Prim t
WHERE NOT EXISTS( SELECT 1 FROM prim t2
WHERE t.Value % t2.Value = 0
AND t.Value != t2. Value)
OPTION (MAXRECURSION 0)
One simple one can be like this
select level id1 from dual connect by level < 2001
minus
select distinct id1 from (select level id1 from dual connect by level < 46) t1 inner join (select level id2 from dual connect by level < 11) t2
on 1=1 where t1.id1> t2.id2 and mod(id1,id2)=0 and id2<>1
Simplest method For SQL Server
DECLARE #range int = 1000, #x INT = 2, #y INT = 2
While (#y <= #range)
BEGIN
while (#x <= #y)
begin
IF ((#y%#x) =0)
BEGIN
IF (#x = #y)
PRINT #y
break
END
IF ((#y%#x)<>0)
set #x = #x+1
end
set #x = 2
set #y = #y+1
end
MySQL QUERY SOLUTION
I have solved this problem in mysql which is following:
SET #range = 1000;
SELECT GROUP_CONCAT(R2.n SEPARATOR '&')
FROM (
SELECT #ctr2:=#ctr2+1 "n"
FROM information_schema.tables R2IS1,
information_schema.tables R2IS2,
(SELECT #ctr2:=1) TI
WHERE #ctr2<#range
) R2
WHERE NOT EXISTS (
SELECT R1.n
FROM (
SELECT #ctr1:=#ctr1+1 "n"
FROM information_schema.tables R1IS1,
information_schema.tables R1IS2,
(SELECT #ctr1:=1) I1
WHERE #ctr1<#range
) R1
WHERE R2.n%R1.n=0 AND R2.n>R1.n
)
Note: No. of information_schema.tables should be increased for more range e.g. if range is 100000 so set the info tables by checking yourself.
--Create Table prime_number_t
create table prime_number_t (
integervalue_c integer not null primary key
);
--Insert Data into table prime_number_t
INSERT ALL
into prime_number_t(integervalue_c) values (1)
into prime_number_t(integervalue_c) values (2)
into prime_number_t(integervalue_c) values (3)
into prime_number_t(integervalue_c) values (4)
into prime_number_t(integervalue_c) values (5)
into prime_number_t(integervalue_c) values (6)
into prime_number_t(integervalue_c) values (7)
into prime_number_t(integervalue_c) values (8)
into prime_number_t(integervalue_c) values (9)
into prime_number_t(integervalue_c) values (10)
SELECT 1 FROM DUAL;
COMMIT;
--Write an SQL statement to determine which of the below numbers are prime numbers
--same query works for REMAINDER function also instead of MOD function
WITH cte_prime_number_t AS
(
select integervalue_c
from prime_number_t
order by integervalue_c
),
cte_maxval AS
(
select max(integervalue_c) AS maxval FROM cte_prime_number_t
),
cte_level AS
(
select LEVEL+1 as lvl
from dual,
cte_maxval
CONNECT BY LEVEL <= cte_maxval.maxval
)
SELECT DISTINCT cpnt.integervalue_c as PrimeNumbers
FROM cte_prime_number_t cpnt
inner join cte_level cl on lvl <= (SELECT maxval FROM cte_maxval)
WHERE NOT EXISTS (
SELECT 1 FROM cte_level cpn
WHERE cpnt.integervalue_c > cpn.lvl AND mod(cpnt.integervalue_c,cpn.lvl) = 0
)
order by PrimeNumbers;
For MySQL 8 or above
/* create a table with one row and that starts with 2 ends at 1000*/
SET cte_max_recursion_depth = 1001; /* works for MySQL 8.0*/
;WITH RECURSIVE sequence AS (
SELECT 1 AS l
UNION ALL
SELECT l + 1 AS value
FROM sequence
WHERE sequence.l < 1000
),
/* create a caretesian product of a number to other numbers uptil this very number
so for example if there is a value 5 in a row then it creates these rows using the table below
(5,2), (5,3), (5,4), (5,5) */
J as (
SELECT (a.l) as m , (b.l) as n
FROM sequence a, sequence b
WHERE b.l <= a.l)
,
/*take a row from column 1 then divide it with other column values but group by column 1 first,
note the completely divisible count*/
f as
( SELECT m , SUM(CASE WHEN mod(m,n) = 0 THEN 1 END) as fact
FROM J
GROUP BY m
HAVING fact = 2
ORDER BY m ASC /*this view return numbers in descending order so had to use order by*/
)
/* this is for string formatting, converting a column to a string with separator &*/
SELECT group_concat(m SEPARATOR '&') FROM f;
This worked for me in MySql:
select '2&3&5&7&11&13&17&19&23&29&31&37&41&43&47&53&59&61&67&71&73&79&83&89&97&101&103&107&109&113&127&131&137&139&149&151&157&163&167&173&179&181&191&193&197&199&211&223&227&229&233&239&241&251&257&263&269&271&277&281&283&293&307&311&313&317&331&337&347&349&353&359&367&373&379&383&389&397&401&409&419&421&431&433&439&443&449&457&461&463&467&479&487&491&499&503&509&521&523&541&547&557&563&569&571&577&587&593&599&601&607&613&617&619&631&641&643&647&653&659&661&673&677&683&691&701&709&719&727&733&739&743&751&757&761&769&773&787&797&809&811&821&823&827&829&839&853&857&859&863&877&881&883&887&907&911&919&929&937&941&947&953&967&971&977&983&991&997';
Well, I know the above one is just hardcoded and you will be able to run the problem but it's not what we should go for as a programmer so here is my solution for oracle:
SELECT LISTAGG(L1,'&') WITHIN GROUP (ORDER BY L1) FROM (Select L1 FROM (SELECT LEVEL L1 FROM DUAL CONNECT BY LEVEL<=1000) Where L1 <> 1 MINUS select L1 from (SELECT LEVEL L1 FROM DUAL CONNECT BY LEVEL<=1000) A , (SELECT LEVEL L2 FROM DUAL CONNECT BY LEVEL<=1000) B Where L2<=L1 and MOD(L1,L2)=0 AND L1<>L2 AND L2<>1);
Worked in Oracle:
SELECT LISTAGG(a,'&')
WITHIN GROUP (ORDER BY a)
FROM(WITH x AS(
SELECT level+1 x
FROM dual
CONNECT BY LEVEL <= 999
)
SELECT x.x as a
FROM x
WHERE NOT EXISTS (
SELECT 1 FROM x y
WHERE x.x > y.x AND remainder( x.x, y.x) = 0
));
SELECT GROUP_CONCAT(distinct PRIME_NUMBER SEPARATOR '&')
FROM (SELECT #prime:=#prime + 1 AS PRIME_NUMBER
FROM information_schema.tables
CROSS JOIN (SELECT #prime:=1) r
WHERE #num <1000
) p
WHERE NOT EXISTS (
SELECT * FROM
(SELECT #divisor := #divisor + 1 AS DIVISOR FROM
information_schema.tables
CROSS JOIN (SELECT #divisor:=1) r1
WHERE #divisor <=1000
) d
WHERE MOD(PRIME_NUMBER, DIVISOR) = 0 AND PRIME_NUMBER != DIVISOR) ;
enter code here
Explanation:
The two inner SELECTs (SELECT #prime and SELECT #divisor) create two lists. Both of them contain numbers from 1 to 1000. The first list is the "list of potential primes" and the second is the "list of divisors"
Then, we iterate over the list of the potential primes (the outer SELECT), and for each number from this list we look for divisors (SELECT * FROM clause) that can divide the number without a reminder and are not equal to the number (WHERE MOD... clause). If at least one such divisor exists, the number is not prime and is not selected (WHERE NOT EXISTS... clause).
The next example is my database.
tb_port
id port
1 80
2 22
3 53
4 3128
5 443
tb_dest
id dest
1 network
2 local
tb_rule
id id_port id_dest
1 1 1
2 2 1
3 3 1
4 4 1
5 5 1
Select:
select dest,group_concat(port) from tb_port a, tb_dest b, tb_rule c where a.id=c.id_port and b.id=c.id_dest group by dest
Result:
network 80,22,53,3128,443
but is not the result I'm looking for, the result would be this.
Select ex:
select dest,group_concat(port limit 2) from tb_port a, tb_dest b, tb_rule c where a.id=c.id_port and b.id=c.id_dest group by dest
result I would like
network 80,22
network 53,3128
network 443
how to achieve this result only with SQL?
Sqlfiddle: http://sqlfiddle.com/#!2/d11807
MySQL doesn't make this kind of query easy, but one (admittedly not very pretty) solution is to use a variable to give each row a sequence number per dest and just group by the row number integer divided by 2 to get two numbers in each group;
SELECT dest, GROUP_CONCAT(port ORDER BY rank) ports
FROM (
SELECT dest, port, (
CASE dest WHEN #curDest
THEN #curRow := #curRow + 1
ELSE #curRow := 1 AND #curDest := dest END) rank
FROM tb_port a
JOIN tb_rule c ON a.id = c.id_port
JOIN tb_dest b ON b.id = c.id_dest,
(SELECT #curRow := 0, #curDest := '') r
ORDER BY dest
) z
GROUP BY FLOOR(rank/2),dest
ORDER BY dest, MIN(rank)
An SQLfiddle to test with.
Here is a stored proc,you just put in the delimiter when you call it
DELIMITER $$
DROP PROCEDURE IF EXISTS explode_table $$
CREATE PROCEDURE explode_table(bound VARCHAR(255))
BEGIN
DECLARE id TEXT;
DECLARE value TEXT;
DECLARE occurance INT DEFAULT 0;
DECLARE i INT DEFAULT 0;
DECLARE splitted_value TEXT;
DECLARE done INT DEFAULT 0;
DECLARE cur1 CURSOR FOR
select dest,group_concat(port) from tb_port a, tb_dest b, tb_rule c
where a.id=c.id_port and b.id=c.id_dest and dest != '' group by dest;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;
DROP TEMPORARY TABLE IF EXISTS table2;
CREATE TEMPORARY TABLE table2(
`id` VARCHAR(255),
`value` VARCHAR(255) NOT NULL
) ENGINE=Memory;
OPEN cur1;
read_loop: LOOP
FETCH cur1 INTO id, value;
IF done THEN
LEAVE read_loop;
END IF;
SET occurance = (SELECT LENGTH(CONCAT(value,bound))
- LENGTH(REPLACE(CONCAT(value,bound), bound, ''))
+1);
SET i=2;
WHILE i <= occurance DO
SET splitted_value =
SUBSTRING_INDEX(SUBSTRING_INDEX(CONCAT(value,bound),bound,i),bound,-2) ;
INSERT INTO table2 VALUES (id, splitted_value);
SET i = i + 2;
END WHILE;
END LOOP;
SELECT * FROM table2;
CLOSE cur1;
END; $$
CALL explode_table(',')