How to use like clause with multiple values in DB2 version 12.01.
SELECT t1.* FROM table1 t1
, ( select (pattern_col) as term from help_table ) t2
WHERE t1.col1 like t2.term
Pattern_col contains n number of values like(%abc%, %xyz%, %nnn%, ...)
Thanks in advance for your time and help.
I tried this solution mentioned in How to use LIKE with IN in DB2?. It works when I use sysdummy table (Oracle equivalent is DUAL)
But when i try to replace the sysdummy1 with actual table values, i get below error.
SQLCODE = -132, ERROR: AN OPERAND OF LIKE IS NOT VALID
I am not able to figure out why it works with sysdummy1 and why not with actual table.
There is nothing wrong with your approach (I guess), but the platform/version you are on may be a problem. Example for Db2 11.5 on LUW:
create table patterns (pid int not null primary key, pattern varchar(100) not null);
insert into patterns (pid, pattern) values (1, '%abc% %xyz% %nnn%');
create table t (val varchar(100) not null primary key);
insert into t (val) values ('xyzabc xyz nnn'),('xyzabc xyz nn');
select t.*
from t
join patterns p
on t.val like p.pattern
where p.pid = 1;
VAL
----------------------------------------------------------------------------------------------------
xyzabc xyz nnn
You can insert multiple patterns like:
delete from patterns;
insert into patterns (pid, pattern)
values (1, '%abc%'), (2, '%xyz%'), (3, '%nnn%');
select t.*
from t
join patterns p
on t.val like p.pattern
where p.pid = 1;
VAL
----------------------------------------------------------------------------------------------------
xyzabc xyz nn
xyzabc xyz nnn
From your comment it appears as if you are using zos. Both LUW and ZOS have regexp abilities that you may want to explore:
REGEXP_LIKE
Related
Am trying to convert below oracle query to postgres,
MERGE INTO table1 g
USING (SELECT distinct g.CDD , d.SGR
from table2 g, table3 d
where g.IDF = d.IDF) f
ON (g.SGR = f.SGR and g.CDD = f.CDD)
WHEN NOT MATCHED THEN
INSERT (SGR, CDD)
VALUES (f.SGR, f.CDD);
I made changes as below compatible to postgres:
WITH f AS (
SELECT distinct g.CDD , d.SGR
from table2 g, table3 d
where g.IDF = d.IDF
),
upd AS (
update table1 g
set
SGR = f.SGR , CDD = f.CDD
FROM f where g.SGR = f.SGR and g.CDD = f.CDD
returning g.CDD, g.SGR
)
INSERT INTO table1(SGR, CDD ) SELECT f.SGR, f.CDD FROM f;
But am doubtful ,my oracle query is not updating any columns if data matched , but am unable to convert it accordingly . Can anyone help me to correct it ?
Assuming you have a primary (or unique) key on (sgr, cdd) you can convert this to an insert ... on conflict statement:
insert into table1 (SGR, CDD)
select distinct g.CDD, d.SGR
from table2 g
join table3 d ON g.IDF = d.IDF
on conflict (cdd, sgr) do nothing;
If you don't have a unique constraint (which bears the question: why?) then a straight-forward INSERT ... SELECT statement should work (which would have worke in Oracle as well).
WITH f AS (
SELECT distinct g.CDD, d.SGR
from table2 g
join table3 d on g.IDF = d.IDF
)
INSERT INTO table1 (SGR, CDD)
SELECT f.SGR, f.CDD
FROM f
WHERE NOT EXISTS (select *
from table1 t1
join f on (t1.sgr, t1.cdd) = (f.cdd, f.sgrf));
Note that this is NOT safe for concurrent execution (and neither is Oracle's MERGE statement). You can still wind up with duplicate values in table1 (with regards to the combination of (sgr,cdd)).
The only sensible way to prevent duplicates is to create a unique index (or constraint) - which would enable you to use the much more efficient insert on conflict. You should really consider that if your business rules disallow duplicates.
Note that I converted your ancient, implicit join in the WHERE clause to a modern, explicit JOIN operator, but it is not required for this to work.
I have comma separated column which represents the ids of emergency type like:
ID | Name
1 | 1,2,3
2 | 1,2
3 | 1
I want to make query to get name of the this value field.
1 - Ambulance
2 - Fire
3 - Police
EXPECTED OUTPUT
1 - Ambulance, Fire, Police
2 - Ambulance, Fire
3 - Ambulance
I just need to write select statement in postgresql to display string values instead of integer values in comma separated.
Comma separated values is bad database design practice, though postgre is so feature rich, that you can handle this task easily.
-- just simulate tables
with t1(ID, Name) as(
select 1 ,'1,2,3' union all
select 2 ,'1,2' union all
select 3 ,'1'
),
t2(id, name) as(
select 1, 'Ambulance' union all
select 2, 'Fire' union all
select 3, 'Police'
)
-- here is actual query
select s1.id, string_agg(t2.name, ',') from
( select id, unnest(string_to_array(Name, ','))::INT as name_id from t1 ) s1
join t2
on s1.name_id = t2.id
group by s1.id
demo
Though, if you can, change your approach. Right database design means easy queries and better performance.
To get the values for each of the ids is a simple query: select * from ;. Once you have the values you will have to parse the strings with a delimiter of ','. then you would have to assign the parsed sting values to the appropriate job titles, and remake the list. Are you writing this in a specific language?
or you could just assign the sorted value to something like 1,2,3 is equal to "some string", 1,2 is equal to "some other string", etc.
Assuming you have a table with the ids and values for Ambulance, Police and Fire, then you can use something like the following.
CREATE TABLE public.test1
(
id integer NOT NULL,
commastring character varying,
CONSTRAINT pk_test1 PRIMARY KEY (id)
);
INSERT INTO public.test1
VALUES (1, '1,2,3'), (2, '1,2'), (3, '1');
CREATE TABLE public.test2
(
id integer NOT NULL,
description character varying,
CONSTRAINT pk_test2 PRIMARY KEY (id)
);
INSERT INTO public.test2
VALUES (1, 'Ambulance'), (2, 'Fire'), (3, 'Police');
with descs as
(with splits as
(SELECT id, split_part(commastring, ',', 1) as col2,
split_part(commastring, ',', 2) as col3, split_part(commastring, ',', 3) as col4 from test1)
select splits.id, t21.description as d1, t22.description as d2, t23.description as d3
from splits
inner join test2 t21 on t21.id::character varying = splits.col2
left join test2 t22 on t22.id::character varying = splits.col3
left join test2 t23 on t23.id::character varying = splits.col4)
SELECT descs.id, CASE WHEN d2 IS NOT NULL AND d3 IS NOT NULL
THEN CONCAT_WS(',', d1,d2,d3) ELSE CASE WHEN d2 IS NOT NULL
THEN CONCAT_WS(',', d1,d2) ELSE d1 END END FROM descs
ORDER BY id;
By way of explanation, I give the create table and insert commands, so that you (and others) can follow the logic. It would help enormously, if you were to do this in your questions, as it saves everyone time and avoids misunderstandings.
My inner CTE then splits the string using split_part. The syntax here is quite simple, field, separator and desired column within the field to be split (so in this case we need one, two and three). I then join the split columns to test2. Note two things here: the first join is an inner join, as there will always be at least one column in the split (I am assuming!!!), whereas the other two are left joins; secondly, the split of a character varying field in turn produces character varying splits, so I have to cast the int id to character varying for the join to work. Doing the cast this way round (i.e. id to character varying rather than character varying to id) means I don't have to bother about nulls. Finally depending on the number of nulls present, I concatenate the results with the given separator. Again I am assuming d1 will always have a value.
HTH
I have a scenario wherein I have to remove all the strings except a or b or c
My sample table is as follows:
Id Product
------------------
1. a,b,Da,c
2. Ty,a,b,c
3. a,sds,b
Sample output
Id Product
----------------
1. a,b,c
2. a,b,c
3. a,b
My current version is Microsoft SQL Server 2008 R2
This should help you out. As I state in the comments, I make use of Jeff Moden's DelimitedSplit8k, as you're using an older version of SQL Server. if you were using 2016+, you would have access to STRING_SPLIT. I also normalise your data; as storing delimited data is almost always a bad idea.
CREATE TABLE #Sample (id int, Product varchar(20));
INSERT INTO #Sample
VALUES (1,'a,b,Da,c'),
(2,'Ty,a,b,c'),
(3,'a,sds,b');
GO
--The first problem you have is you're storing delimited data
--You really should be storing each item on a separate row.
--This is, however, quite easy to do. i'm going to use a different
--table, however, you can change this fairly easily for your
--needs.
CREATE TABLE #Sample2 (id int, Product varchar(2));
GO
--You can split the data out by using a Splitter.
--My personal preference is Jeff Moden's DelimitedSplit8K
--which I've linked to above.
INSERT INTO #Sample2 (id, Product)
SELECT id, Item AS Product
FROM #Sample S
CROSS APPLY dbo.DelimitedSplit8K(S.Product,',') DS
WHERE DS.Item IN ('a','b','c');
GO
--And hey presto! Your normalised data, and without the unwanted values
SELECT *
FROM #Sample2;
GO
DROP TABLE #Sample;
DROP TABLE #Sample2;
If you have to keep the delimited format, you can use STUFF and FOR XML PATH:
WITH Split AS(
SELECT id,
Item AS Product,
ItemNumber
FROM #Sample S
CROSS APPLY dbo.DelimitedSplit8K(S.Product,',') DS
WHERE DS.Item IN ('a','b','c'))
SELECT id,
STUFF((SELECT ',' + Product
FROM Split sq
WHERE sq.id = S.id
ORDER BY ItemNumber
FOR XML PATH('')),1,1,'')
FROM Split S
GROUP BY id;
This also will do the thing, using xml only:
select * into #t from (values('a,b,Da,c'),('Ty,a,b,c'),('a,sds,b'))v(Product)
;
with x as (
SELECT t.Product, st.sProduct
FROM #t t
cross apply (
SELECT CAST(N'<root><r>' + REPLACE(t.Product,',', N'</r><r>') + N'</r></root>' as xml) xProduct
)xt
cross apply (
select CAST(r.value('.','NVARCHAR(MAX)') as nvarchar) sProduct
from xt.xProduct.nodes(N'//root/r') AS RECORDS(r)
) st
where st.sProduct in ('a', 'b', 'c')
)
select distinct x.Product, REVERSE(SUBSTRING(REVERSE(cleared.cProduct), 2, 999)) cleared
from x
cross apply ( select (
select distinct ref.sProduct + ','
from x ref
where ref.Product = x.Product
for xml path('') )
)cleared(cProduct)
;
drop table #t
I've seen a lot of post on multiple JOIN but it didn't help me in my case.
Consider that I have three tables and two cross-reference tables. That's the difference with the others posts where they had multiple tables but one cross-reference table in the FROM.
Table1 -> cross-ref1 <- table2 -> cross-ref2 <- table3
My version of Postgresql is : 9.0.11, and I'm working with W7 64 bits.
My request is the following stuff :
Select [columns] from cross-ref1, cross-ref2
INNER JOIN table1 ON table1.id_table1=cross-ref1.ref_id_table1
INNER JOIN table2 ON table2.id=cross-ref1.ref_id_table2
INNER JOIN table2 On table2.id_table2=cross-ref2.ref_id_table2
INNER JOIN table3 ON table3.id_table3=cross-ref2.ref_id_table3
The error message is : "Table name is specified more than once."
Can you explain me the error ?
Thanks
Cross-reference tables need separate columns for each side of the reference. An xref table with just one column makes no sense, as it can only refer to rows with the same ID on each side.
A typical setup would be:
CREATE TABLE a (
id integer primary key,
avalue text not null
);
CREATE TABLE b (
id integer primary key,
bvalue text not null
);
CREATE TABLE ab (
a_id integer references a(id),
b_id integer references b(id),
PRIMARY KEY(a_id, b_id)
);
Given sample data:
INSERT INTO a(id, avalue) VALUES
(1, 'a1'), (2, 'a2'), (3, 'a3'), (4, 'a4');
INSERT INTO b(id, bvalue) VALUES
(41, 'b1'), (42, 'b2'), (43, 'b3');
INSERT INTO ab(a_id, b_id) VALUES
(1, 41), (1, 42), (2, 43);
You'd find the pairings of a and b with:
SELECT avalue, bvalue
FROM a
INNER JOIN ab ON (a.id = ab.a_id)
INNER JOIN b ON (b.id = ab.b_id);
The crucial thing here is that you're joining on ab.a_id on the a side, and ab.b_id on the b side. Observe demo here: http://sqlfiddle.com/#!12/3228a/1
This is pretty much "many-to-many table relationships 101", so it might be worth doing some more study of introductory SQL and relational database tutorials and documentation.
You can't use the same table name twice (table2). In this case you need to use aliases like t1, t2a, t2b, ...
SELECT
...
FROM
table1 AS t1
INNER JOIN table2 AS t2a
ON t2a.id= ...
INNER JOIN table2 AS t2b
ON t2b.id= ...
INNER JOIN table3 AS t3
ON t3.id= ...
...
Now you can join whatever you want, how many times you want etc.
You have to explain what result you want to have. For example the following SQL is valid from syntax point of view, not sure about business point of view:
-- this will create sample data with 5 tables
with
crossref1(ref_id) as (VALUES (1),(2),(3)),
crossref2 (ref_id) as (VALUES (2),(3),(4)),
table1 (ref_id) as (VALUES (3),(4),(5)),
table2 (ref_id) as (VALUES (1),(2),(3)),
table3 (ref_id) as (VALUES (1),(2),(3))
-- valid SQL based on your example
select * from
crossref1
cross join crossref2
join table1 on table1.ref_id=crossref1.ref_id
join table2 as t2_1 on t2_1.ref_id=crossref1.ref_id
join table2 as t2_2 on t2_2.ref_id=crossref2.ref_id
join table3 on table3.ref_id=crossref2.ref_id
With your SQL there are two problems:
You have two references to table2, you have to add alias
You have to use cross join syntax instead of ,
If you would like to understand how with works (how I created sample data), PostgreSQL has excellent documentation on this.
I'll just put this in layman's terms since I'm a complete noobie:
I have 2 tables A and B, both having 2 columns of interest namely: employee_number and salary.
What I am looking to do is to extract rows of 'combination' of employee_number and salary from A that are NOT present in B, but each of employee_number and salary should be present in both.
I am looking to doing it with the 2 following conditions(please forgive the wrong function
names.. this is just to present the problem 'eloquently'):
1.) A.unique(employee_number) exists in B.unique(employee_number) AND A.unique(salary)
exists in B.unique(salary)
2.) A.concat(employee_number,salary) <> B.concat(employee_number,salary)
Note: A and B are in different databases, so I'm looking to use dblink to do this.
This is what I tried doing:
SELECT distinct * FROM dblink('dbname=test1 port=5432
host=test01 user=user password=password','SELECT employee_number,salary, employee_number||salary AS ENS FROM empsal.A')
AS A(employee_number int8, salary integer, ENS numeric)
LEFT JOIN empsalfull.B B on B.employee_number = A.employee_number AND B.salary = A.salary
WHERE A.ENS not in (select distinct employee_number || salary from empsalfull.B)
but it turned out to be wrong as I had it cross-checked by using spreadsheets and I don't get the same result.
Any help would be greatly appreciated. Thanks.
For easier understanding I left out the dblink.
Because, the first one selects lines in B that equal the employeenumber in A as well as the salery in A, so their concatenated values will equal as well (if you expect this to not be true, please provide some test data).
SELECT * from firsttable A
LEFT JOIN secondtable B where
(A.employee_number = B.employee_number AND a.salery != b.salery) OR
(A.salery = B.salery AND A.employee_number != B.employee_number)
If you have troubles with lines containing nulls, you might also try somthing like this:
AND (a.salery != b.salery OR (a.salery IS NULL AND b.salery IS NOT NULL) or (a.salery IS NOT
NULL and b.salery IS NULL))
I think you're looking for something along these lines.
(Sample data)
create table A (
employee_number integer primary key,
salary integer not null
);
create table B (
employee_number integer primary key,
salary integer not null
);
insert into A values
(1, 20000),
(2, 30000),
(3, 20000); -- This row isn't in B
insert into B values
(1, 20000), -- Combination in A
(2, 20000), -- Individual values in A
(3, 50000); -- Only emp number in A
select A.employee_number, A.salary
from A
where (A.employee_number, A.salary) NOT IN (select employee_number, salary from B)
and A.employee_number IN (select employee_number from B)
and A.salary IN (select salary from B)
output: 3, 20000