I need to do an insert and check for each row if the field "partita_iva" is already in this table, if yes the field "flag" must be 1, if not then must be 0. I did this, but it set 1 for all the rows, even if should be 1 just for one row
INSERT INTO tab2(id, flag)
select newid,
CASE
WHEN EXISTS(SELECT * FROM tab1 WHERE partita_iva IN(SELECT partita_iva FROM tab2))
THEN 1
ELSE 0
END AS flag
from tab1
It can probably be simplified.
INSERT INTO tab2 (id, flag)
SELECT t1.newid
, IIF(EXISTS(SELECT 1 FROM tab2 t2 WHERE t2.partita_iva = t1.partita_iva), 1, 0) AS flag
FROM tab1 t1
Your current query logic seems correct to me, but you can correlate your sub-query :
INSERT INTO tab2(id, flag)
SELECT NEWID(), CASE WHEN EXISTS(SELECT 1
FROM tab2 t2
WHERE t2.partita_iva = t1.partita_iva
)
THEN 1 ELSE 0
END AS flag
FROM tab1 t1;
NEWID() is a function that will creates a unique value of type uniqueidentifier.
As a total stab in the dark:
INSERT INTO tab2(Id,Flag)
SELECT newid, --Do you mean NEWID()?
CASE WHEN EXISTS(SELECT 1 FROM tab2 T2 WHERE T2.partita_iva = T1.partita_iva) THEN 1 ELSE 0 END
FROM tab1 T1;
Related
I have a view which contains a cast statement for one column. This cast statement contains a case statement. This statement works. The result of this statement is 1, 2, or 3.
From here, I need to use the result from the previous case statement (I used a WITH statement and it doesn't work) to determine the value of the column. A simple case statement that assigns yes, no or null to the above statement's value (1,2, or 3)
ANY help is appreciated. Thank you.
Example using pseudo-code:
CAST (
WITH case_output
AS(
SELECT
CASE
WHEN EXISTS
(select from table where blah blah)
THEN
(select column from that table)
ELSE
(select from some another table)
END
)
CASE
WHEN case_output = 1
THEN 'Yes'
WHEN case_output = 2
THEN 'No'
else
NULL
AS VARCHAR2 (10))
column_name,
.... [rest of query]
You're mixing up the query name and the column name of the WITH clause. For example, it's
WITH my_query AS (SELECT c1 AS my_column FROM t1)
SELECT my_column FROM my_query;
Secondly, you'll always need a FROM clause in Oracle's SQL. Use the dummy table DUAL as stand-in:
SELECT CASE WHEN ... THEN END AS my_column
FROM DUAL;
Minimal working example:
CREATE TABLE t1 (c1 INT);
CREATE TABLE t2 (c2 INT);
INSERT INTO t1 VALUES (1);
INSERT INTO t2 VALUES (2);
WITH case_query AS (
SELECT CASE WHEN EXISTS (SELECT * FROM t1 WHERE c1=100)
THEN (SELECT c1 FROM t1)
ELSE (SELECT c2 FROM t2)
END AS case_output
FROM dual)
SELECT CASE case_output
WHEN 1 THEN 'Yes'
WHEN 2 THEN 'No'
ELSE NULL
END second_case_output
FROM case_query;
I have two queries, first is a check if value exists in table1, if yes - I'm updating a value in table2, otherwise I return 0 as a count of found values.
It happens really often and I wish I could do that with one query. How would the query look like then?
Maybe you can try something like this. A RETURNING clause will return rows if at least one row was updated in the with clause. It is then verified by an exists check in the select part.
with upd as
(
update table2 t2 set col = 'value4'
where id = ? and exists ( select 1 from table1 t1 where id = ? ) returning *
)
select exists ( select 1 from upd ) :: int as "updated";
This query when run will return 0 ( integer equivalent of boolean false ) when no rows exist and 1 when at least one row was updated.
DEMO
You can join table1 & table2 and then update the value from table2 with table1.
I am looking to count the number of times set of values occurred in a table. These values could occur in up to 10 different columns. I need to increment the count regardless of which column it is in. I know how I could count if they were all in the same column but not spanning multiple columns.
Values can be added in any order. I have about a thousand
Cpt1 Cpt2 Cpt3 Cpt4 Cpt5
63047 63048 63048 NULL NULL
I would want to for this row I'd expect this as the result
63047 1
63048 2
You could use a union all call to treat them as one column:
SELECT col, COUNT(*)
FROM (SELECT col1 FROM mytable
UNION ALL
SELECT col2 FROM mytable
UNION ALL
SELECT col3 FROM mytable
-- etc...
) t
GROUP BY col
It's not entirely clear what your table exactly looks like, but I'm guessing that what you're looking for is:
SELECT row_count = COUNT(*),
row_count_with_given_value = SUM ( CASE WHEN field1 = 'myValue' THEN 1
WHEN field2 = 'myValue' THEN 1
WHEN field3 = 'myValue' THEN 1
WHEN field4 = 'myValue' THEN 1 ELSE 0 END)
FROM myTable
Assuming the fieldx columns are not NULL-able, you could write it like this too:
SELECT row_count = COUNT(*),
row_count_with_given_value = SUM ( CASE WHEN 'myValue' IN (field1, field2, field3, field4) THEN 1 ELSE 0 END)
FROM myTable
Something like this might work (after adapting to your value domain and data types):
create table t1
(i1 int,
i2 int,
i3 int);
insert into t1 values (1,0,0);
insert into t1 values (1,1,1);
insert into t1 values (1,0,0);
declare #i int = 0;
select #i = #i + i1 + i2 + i3 from t1;
print #i;
drop table t1;
Output is: 5
Many databases support lateral joins, of one type of another. These can be used to simplify this operation. Using the SQL Server/Oracle 12C syntax:
select v.cpt, count(*)
from t cross apply
(values (cpt1), (cpt2), . . .
) v(cpt)
where cpt is not null
group by v.cpt;
I have a scenario where I have to search value of column 1 in first table to see whether it matches some value in another table.
This should continue in a loop until the last row on first table has been compared.
No loops needed. You can do this easily as a set based operation using exists()
select *
from FirstTable
where exists (
select 1
from SecondTable
where FirstTable.Column1 = SecondTable.Column1
);
To find the opposite, where the row in the first table does not have a match based on Column1, you can use not exists()
select *
from FirstTable
where not exists (
select 1
from SecondTable
where FirstTable.Column1 = SecondTable.Column1
);
If you want to identify which rows have a match and don't you can use:
select FirstTable.*
, MatchFound = case when x.Column1 is null then 'No' else 'Yes' end
, x.Column1
from FirstTable
outer apply (
select top 1
*
from SecondTable
where FirstTable.Column1 = SecondTable.Column1
) as x
I have a table that has thousands of rows in. I need to check if certain values exists in the table or not.
I want to list all the bar codes I am searching with a flag of true or false returned if there is one.
I have come up with this so far:
SELECT CASE WHEN EXISTS (
SELECT *
FROM TABLE
WHERE Coulmn in ('a','b', 'c', 'd', 'e', 'f', 'g')
)
THEN CAST(1 AS BIT)
ELSE CAST(0 AS BIT) END
This however just returns a value of 1.
So in the table I have
coulmn
----------
A
B
D
E
F
G
I want to do a search that returns the following
Coulmn | Exsists
-----------------
A | True
B | True
C | False
D | True
E | True
F | True
G | True
You can use a query like the following:
SELECT t1.v,
CASE WHEN t2.col IS NOT NULL THEN 'true' ELSE 'false' END AS Exists
FROM (
SELECT 'a' AS v UNION ALL SELECT 'b' UNION ALL SELECT 'c' UNION ALL SELECT 'd'
UNION ALL SELECT 'e' UNION ALL SELECT 'f' UNION ALL SELECT 'g') AS t1
LEFT JOIN mytable AS t2 ON t1.v = t2.col
This works:
SELECT *, CASE WHEN (Column in ('1','2')) THEN CAST(1 AS BIT) ELSE CAST(0 AS BIT) END AS result_field
FROM TABLE;
NOTE: Tested in PostgreSQL
As it's written, the outer select is select case when exists () then 1 else 0 end... so it is only going to return one row. The outer select must include "Column" AND "Exists" (select column, ...) to return two columns.
A "where" clause will never return a "false" like this, though, because "column" has to be in a real table for the query to actually return it. As #jarlh says, you'll need a helper table to store the columns you're looking for:
Create table SearchColumns (SearchColumn char(1));
insert into SearchColumns (SearchColumn)
values ('A'), ('B'), ('C'), ('D'), ('E'), ('F'), ('G'), ('H')
Then you can do the If Exists to your table from that table to see which values are in or not in:
select SearchColumn, case when exists
(select * from TABLE where Table.Column = SearchColumns.SearchColumn)
then 'True' else 'False' end as ExistsStatus
from SearchColumns
I think that will get you what you want. This gets a) Only one record per column no matter how many times it occurs in your table and b) "True" and "False" for every column value you're looking for. If you really wanted a Bit, you can use 0 and 1 and the casting from the original query, but they actually show "0" and "1"; and c) this should work no matter how many values you have.
(Note, I assumed some of those were spelling errors, so I made adjustments, but they were consistent so I'm not certain).
With the help form above I created a temp table and then implemented one of the soultions shared.
CREATE TABLE #Temp
(
Barcode VARCHAR (100)
)
INSERT INTO #Temp
VALUES
(1),
(2),
(3),
(4 )
select barcode, case when exists
(select * from CIPKORHHTProductDetails where CIPKORHHTProductDetails.Barcode = #temp.barcode)
then 'True' else 'False' end as ExistsStatus
from #temp order by ExistsStatus DESC