Taking the "transpose" of a table using SQL - sql

I don't know if there is a name for this operation but it's similar to the transpose in linear algebra.
Is there a way to turn an 1 by n table T1 such as
c_1|c_2|c_3|...|a_n
-------------------
1 |2 |3 |...|n
Into a n by 2 table like the following
key|val
-------
c_1|1
b_2|2
c_3|3
. |.
. |.
a_n|n
I am assuming that each column c_i in T1 can be unlikely identified.

Basically, you need to UNPIVOT this data, you can perform this using a UNION ALL:
select 'c_1' col, c_1 value
from yourtable
union all
select 'c_2' col, c_2 value
from yourtable
union all
select 'c_3' col, c_3 value
from yourtable

#swasheck then I'd guess they'd have to read the column names in to a list
mylistobject = SELECT sql FROM sqlite_master WHERE tbl_name = 'table_name' AND type = 'table'
Create the new table with the column name is primary key, then value, and then iterate on the list, something a lot less messy than this in Python
for columnName in list:
row = cursor.execute('SELECT ' + str(value) + 'FROM tableToBeTransposed WHERE COLUMN = ' + str(c_i) + ';').fetchone()
cursor.execute('INSERT INTO newTable(c_i, values), (?,?)' (columnName, value))

Related

Condition check to get output

I have 2 tables name and match. The name and match table have columns type.
The columns and data in the name table
ID| type |
--| ---- |
1| 1ABC |
2| 2DEF |
3| 3DEF |
4| 4IJK |
The columns and data in match table is
type
DATA
NOT %ABC% AND NOT %DEF%
NOT ABC AND NOT DEF
%DEF%
DEF ONLY
NOT %DEF% AND NOT %IJK%
NOT DEF AND NOT IJK
I have tried using case statement. The first 3 characters will be NOT if there is a NOT in the type in match table.
The below query is giving me a missing keyword error. I am not sure what I am missing here
SELECT s.id, s.type, m.data
where case when substr(m.type1,3)='NOT' then s.type not in (REPLACE(REPLACE(m.type,'NOT',''),'AND',','))
ELSE s.type in (m.type) end
from source s, match m;
I need the output to match the type in source column and display the data in match column.
The output should be
ID|type|DATA
1 |1ABC|NOT DEF AND NOT IJK
2 |2DEF|DEF ONLY
3 |3DEF|DEF ONLY
4 |4IJK|NOT ABC AND NOT DEF
The biggest problem with your attempted query seems to be that SQL requires the WHERE clause to come after the FROM clause.
But your query is flawed in other ways as well. Although it can have complicated logic within it, including subqueries, a CASE statement must ultimately return a constant. Conditions within it are not applied as if they are in a WHERE clause of the main query (like you appear to be trying to do).
My recommendation would be to not store the match table as you currently are. It seems much preferable to have something that contains each condition you want to evaluate. Assuming that's not possible, I suggest a CTE (or even a view) that breaks it down that way first.
This query (based on Nefreo's answer for breaking strings into multiple rows)...
SELECT
data,
regexp_count(m.type, ' AND ') + 1 num,
CASE WHEN REGEXP_SUBSTR(m.type,'(.*?)( AND |$)',1,levels.column_value) like 'NOT %' THEN 1 ELSE 0 END negate,
replace(replace(REGEXP_SUBSTR(m.type,'(.*?)( AND |$)',1,levels.column_value), 'NOT '), ' AND ') match
FROM match m INNER JOIN
table(cast(multiset(select level from dual connect by level <= regexp_count(m.type, ' AND ') + 1) as sys.OdciNumberList)) levels
ON 1=1
... breaks your match table into something more like:
DATA
NUM
NEGATE
MATCH
NOT ABC AND NOT DEF
2
1
%ABC%
NOT ABC AND NOT DEF
2
1
%DEF%
DEF ONLY
1
0
%DEF%
NOT DEF AND NOT IJK
2
1
%DEF%
NOT DEF AND NOT IJK
2
1
%IJK%
So we now know each specific like condition, whether it should be negated, and the number of conditions that need to be matched for each MATCH row. (For simplicity, I am using match.data as essentially a key for this since it is unique for each row in match and is what we want to return anyway, but if you were actually storing the data this way you'd probably use a sequence of some sort and not repeat the human-readable text.)
That way, your final query can be quite simple:
SELECT name.id, name.type, criteria.data
FROM name INNER JOIN criteria
ON
(criteria.negate = 0 AND name.type LIKE criteria.match)
OR
(criteria.negate = 1 AND name.type NOT LIKE criteria.match)
GROUP BY name.id, name.type, criteria.data
HAVING COUNT(*) = MAX(criteria.num)
ORDER BY name.id
The conditions in the ON do the appropriate LIKE or NOT LIKE (matches one condition from the CRITERIA view/CTE), and the condition in the HAVING makes sure we had the correct number of total matches to return the row (makes sure we matched all the conditions in one row of the MATCH table).
You can see the entire thing...
WITH criteria AS
(
SELECT
data,
regexp_count(m.type, ' AND ') + 1 num,
CASE WHEN REGEXP_SUBSTR(m.type,'(.*?)( AND |$)',1,levels.column_value) like 'NOT %' THEN 1 ELSE 0 END negate,
replace(replace(REGEXP_SUBSTR(m.type,'(.*?)( AND |$)',1,levels.column_value), 'NOT '), ' AND ') match
FROM match m INNER JOIN
table(cast(multiset(select level from dual connect by level <= regexp_count(m.type, ' AND ') + 1) as sys.OdciNumberList)) levels
ON 1=1
)
SELECT name.id, name.type, criteria.data
FROM name INNER JOIN criteria
ON
(criteria.negate = 0 AND name.type LIKE criteria.match)
OR
(criteria.negate = 1 AND name.type NOT LIKE criteria.match)
GROUP BY name.id, name.type, criteria.data
HAVING COUNT(*) = MAX(criteria.num)
ORDER BY name.id
... working in this fiddle.
As a one-off, I don't think this is significantly different than the other answer already provided, but I wanted to do this since I think this is probably more maintainable if the complexity of your conditions changes.
It already handles arbitrary numbers of conditions, mixes of NOT and not-NOT within the same row of MATCH, and allows for the % signs (for the like) to be placed arbitrarily (e.g. startswith%, %endswith, %contains%, start%somewhere%end, exactmatch should all work as expected). If in the future you want to add different types of conditions or handle ORs, I think the general ideas here will apply.
Not knowing the possible other rules for selecting rows, just with your data from the question, maybe you could use this:
WITH
tbl_name AS
(
Select 1 "ID", '1ABC' "A_TYPE" From Dual Union All
Select 2 "ID", '2DEF' "A_TYPE" From Dual Union All
Select 3 "ID", '3DEF' "A_TYPE" From Dual Union All
Select 4 "ID", '4IJK' "A_TYPE" From Dual
),
tbl_match AS
(
Select 'NOT %ABC% AND NOT %DEF%' "A_TYPE", 'NOT ABC AND NOT DEF' "DATA" From Dual Union All
Select '%DEF%' "A_TYPE", 'DEF ONLY' "DATA" From Dual Union All
Select 'NOT %DEF% AND NOT %IJK%' "A_TYPE", 'NOT DEF AND NOT IJK' "DATA" From Dual
)
Select
n.ID "ID",
n.A_TYPE,
m.DATA
From
tbl_match m
Inner Join
tbl_name n ON (1=1)
Where
(
INSTR(m.A_TYPE, 'NOT %' || SubStr(n.A_TYPE, 2) || '%', 1, 1) = 0
AND
INSTR(m.A_TYPE, 'NOT %' || SubStr(n.A_TYPE, 2) || '%', 1, 2) = 0
AND
Length(m.A_TYPE) > Length(SubStr(n.A_TYPE, 2)) + 2
)
OR
(
Length(m.A_TYPE) = Length(SubStr(n.A_TYPE, 2)) + 2
AND
'%' || SubStr(n.A_TYPE, 2) || '%' = m.A_TYPE
)
Order By n.ID
Result:
ID
A_TYPE
DATA
1
1ABC
NOT DEF AND NOT IJK
2
2DEF
DEF ONLY
3
3DEF
DEF ONLY
4
4IJK
NOT ABC AND NOT DEF
Any other format of condition should be evaluated separately ...
Regards...
WITH match_cte AS (
SELECT m.data
,m.type
,decode(instr(m.type,'NOT')
,1 -- found at position 1
,0
,1) should_find_str_1
,substr(m.type
,instr(m.type,'%',1,1) + 1
,instr(m.type,'%',1,2) - instr(m.type,'%',1,1) - 1) str_1
,decode(instr(m.type,'NOT',instr(m.type,'%',1,2))
,0 -- no second NOT
,1
,0) should_find_str_2
,substr(m.type
,instr(m.type,'%',1,3) + 1
,instr(m.type,'%',1,4) - instr(m.type,'%',1,3) - 1) str_2
FROM match m
)
SELECT s.id
,s.type
,m.data
FROM source s
CROSS JOIN match_cte m
WHERE m.should_find_str_1 = sign(instr(s.type,m.str_1))
AND (m.str_2 IS NULL
OR m.should_find_str_2 = sign(instr(s.type, m.str_2))
)
ORDER BY s.id, m.data
MATCH_CTE
|DATA|TYPE|SHOULD_FIND_STR_1|STR_1|SHOULD_FIND_STR_2|STR_2|
|-|-|-|-|-|-|
|NOT ABC AND NOT DEF|NOT %ABC% AND NOT %DEF%|0|ABC|0|DEF|
|DEF|%DEF%|1|DEF|1|NULL|
|NOT DEF AND NOT IJK|NOT %DEF% AND NOT %IJK%|0|DEF|0|IJK|

How to use LIKE with ANY in BigQuery?

I would like to use the LIKE ANY operator to exclude rows based on an array of substrings, but BigQuery does not recognize it.
declare unlaunched_clistings array<string>;
set unlaunched_clistings = {unlaunched_clistings} ;
select * from {p}.simeon_logs.process_errors e
where not e.message like any(unlaunched_clistings)
Error : LIKE ANY is not supported at [8:32]
Is there any workaround for this?
LIKE ANY is not supported, however you can use following 2 ways:
Use LIKE with ORs between them
WITH table AS (
SELECT 'abc' as col union all
SELECT 'xzy' as col
)
SELECT col
FROM TABLE
WHERE (col like '%abc%'
OR col like '%cde%' OR col like '%something%')
User RegEx
WITH table AS (
SELECT 'abc' as col
UNION ALL
SELECT 'xzy' as col
)
SELECT col
FROM TABLE
WHERE REGEXP_CONTAINS(col
, 'abc|cde|something')
Above both will give you abc row.

How to transpose row to column in Postgres 9.5?

I have this table in input, it contains always only three rows.
| data |
--------
| X |
| Y |
| Z |
And I want this output:
| data1| data2 | data3 |
-------+-------+-------+
| X | Y | Z |
I have tried to use the crosstab function, but as far as I understand it need more information, like a category column and a row_name column. I don't have them.
Is possible to transpose this table?
You don't need a crosstab function to do this, use just a simple PIVOT query:
SELECT max( case rn when 1 then data end ) as data1,
max( case rn when 2 then data end ) as data2,
max( case rn when 3 then data end ) as data3
FROM (
SELECT *,
row_number() over ( ORDER BY data ) rn
FROM table1
) x
Demo: http://sqlfiddle.com/#!15/bead8/4
There is one pitfall in this query you need to think about.
The database table is by definition an unordered set ot tuples, and hardly any database guarantees an ordering of the rows unless an ORDER BY clause is specified in the SELECT statement that queries the table.
Because of this the query uses ORDER BY data clause to order rows in such a way, that X will be put to data1 column, Y to data2 and Z to data3, in this order (becauce X < Y < Z).
You need to change this clause If you need to use some other order (or maybe some other column of this table to determine this order).
For fixed columns/rows count:
select
data[1] as data1,
data[2] as data2,
data[3] as data3
from
(select array_agg(data) as data from t) as t;
For variable columns/rows count (only one from many possibilities):
create function prepare_statement(in p_name text, in p_body text) returns void as $$
declare
s text;
begin
s := 'prepare ' || p_name || ' as ' || p_body;
execute s;
return;
end; $$ language plpgsql;
and then:
select prepare_statement('foo', (
select
'select ' ||
string_agg('data['||i||'] as data'||i, ', ') ||
' from (select array_agg(data) as data from t) as t'
from generate_series(1, (select count(*) from t)) n(i))
);
execute foo;
-- deallocate foo; -- to deallocate previously prepared statement
Read more about
arrays
array_agg function
prepare/execute/deallocate statements

SQL query to get column names if it has specific value

I have a situation here, I have a table with a flag assigned to the column names(like 'Y' or 'N'). I have to select the column names of a row, if it have a specific value.
My Table:
Name|sub-1|sub-2|sub-3|sub-4|sub-5|sub-6|
-----------------------------------------
Tom | Y | | Y | Y | | Y |
Jim | Y | Y | | | Y | Y |
Ram | | Y | | Y | Y | |
So I need to get, what are all the subs are have 'Y' flag for a particular Name.
For Example:
If I select Tom I need to get the list of 'Y' column name in query output.
Subs
____
sub-1
sub-3
sub-4
sub-6
Your help is much appreciated.
The problem is that your database model is not normalized. If it was properly normalized the query would be easy. So the workaround is to normalize the model "on-the-fly" to be able to make the query:
select col_name
from (
select name, sub_1 as val, 'sub_1' as col_name
from the_table
union all
select name, sub_2, 'sub_2'
from the_table
union all
select name, sub_3, 'sub_3'
from the_table
union all
select name, sub_4, 'sub_4'
from the_table
union all
select name, sub_5, 'sub_5'
from the_table
union all
select name, sub_6, 'sub_6'
from the_table
) t
where name = 'Tom'
and val = 'Y'
The above is standard SQL and should work on any (relational) DBMS.
Below code works for me.
select t.Subs from (select name, u.subs,u.val
from TableName s
unpivot
(
val
for subs in (sub-1, sub-2, sub-3,sub-4,sub-5,sub-6,sub-7)
) u where u.val='Y') T
where t.name='Tom'
Somehow I am near to the solution. I can get for all rows. (I just used 2 columns)
select col from ( select col, case s.col when 'sub-1' then sub-1 when 'sub-2' then sub-2 end AS val from mytable cross join ( select 'sub-1' AS col union all select 'sub-2' ) s ) s where val ='Y'
It gives the columns for all row. I need the same data for a single row. Like if I select "Tom", I need the column names for 'Y' value.
I'm answering this under a few assumptions here. The first is that you KNOW the names of the columns of the table in question. Second, that this is SQL Server. Oracle and MySql have ways of performing this, but I don't know the syntax for that.
Anyways, what I'd do is perform an 'UNPIVOT' on the data.
There's a lot of parans there, so to explain. The actual 'unpivot' statement (aliased as UNPVT) takes the data and twists the columns into rows, and the SELECT associated with it provides the data that is being returned. Here's I used the 'Name', and placed the column names under the 'Subs' column and the corresponding value into the 'Val' column. To be precise, I'm talking about this aspect of the above code:
SELECT [Name], [Subs], [Val]
FROM
(SELECT [Name], [Sub-1], [Sub-2], [Sub-3], [Sub-4], [Sub-5], [Sub-6]
FROM pvt) p
UNPIVOT
(Orders FOR [Name] IN
([Name], [Sub-1], [Sub-2], [Sub-3], [Sub-4], [Sub-5], [Sub-6])
)AS unpvt
My next step was to make that a 'sub-select' where I could find the specific name and val that was being hunted for. That would leave you with a SQL Statement that looks something along these lines
SELECT [Name], [Subs], [Val]
FROM (
SELECT [Name], [Subs], [Val]
FROM
(SELECT [Name], [Sub-1], [Sub-2], [Sub-3], [Sub-4], [Sub-5], [Sub-6]
FROM pvt) p
UNPIVOT
(Orders FOR [Name] IN
([Name], [Sub-1], [Sub-2], [Sub-3], [Sub-4], [Sub-5], [Sub-6])
)AS unpvt
) AS pp
WHERE 1 = 1
AND pp.[Val] = 'Y'
AND pp.[Name] = 'Tom'
select col from (
select col,
case s.col
when 'sub-1' then sub-1
when 'sub-2' then sub-2
when 'sub-3' then sub-3
when 'sub-4' then sub-4
when 'sub-5' then sub-5
when 'sub-6' then sub-6
end AS val
from mytable
cross join
(
select 'sub-1' AS col union all
select 'sub-2' union all
select 'sub-3' union all
select 'sub-4' union all
select 'sub-5' union all
select 'sub-6'
) s on name="Tom"
) s
where val ='Y'
included the join condition as
on name="Tom"

T-SQL Comma delimited value from resultset to in clause in Subquery

I have an issue where in my data I will have a record returned where a column value will look like
-- query
Select col1 from myTable where id = 23
-- result of col1
111, 104, 34, 45
I want to feed these values to an in clause. So far I have tried:
-- Query 2 -- try 1
Select * from mytableTwo
where myfield in (
SELECT col1
from myTable where id = 23)
-- Query 2 -- try 2
Select * from mytableTwo
where myfield in (
SELECT '''' +
Replace(col1, ',', ''',''') + ''''
from myTable where id = 23)
-- query 2 test -- This works and will return data, so I verify here that data exists
Select * from mytableTwo
where myfield in ('111', '104', '34', '45')
Why aren't query 2 try 1 or 2 working?
You don't want an in clause. You want to use like:
select *
from myTableTwo t2
where exists (select 1
from myTable t
where id = 23 and
', '+t.col1+', ' like '%, '+t2.myfield+', %'
);
This uses like for the comparison in the list. It uses a subquery for the value. You could also phrase this as a join by doing:
select t2.*
from myTableTwo t2 join
myTable t
on t.id = 23 and
', '+t.col1+', ' like '%, '+t2.myfield+', %';
However, this could multiply the number of rows in the output if there is more than one row with id = 23 in myTable.
If you observe closely, Query 2 -- try 1 & Query 2 -- try 2 are considered as single value.
like this :
WHERE myfield in ('111, 104, 34, 45')
which is not same as :
WHERE myfield in ('111', '104', '34', '45')
So, If you intend to filter myTable rows from MyTableTwo, you need to extract the values of fields column data to a table variable/table valued function and filter the data.
I have created a table valued function which takes comma seperated string and returns a table value.
you can refer here T-SQL : Comma separated values to table
Final code to filter the data :
DECLARE #filteredIds VARCHAR(100)
-- Get the filter data
SELECT #filteredIds = col1
FROM myTable WHERE id = 23
-- TODO : Get the script for [dbo].[GetDelimitedStringToTable]
-- from the given link and execute before this
SELECT *
FROM mytableTwo T
CROSS APPLY [dbo].[GetDelimitedStringToTable] ( #filteredIds, ',') F
WHERE T.myfield = F.Value
Please let me know If this helps you!
I suppose col is a character type, whose result would be like like '111, 104, 34, 45'. If this is your situation, it's not the best of the world (denormalized database), but you can still relate these tables by using character operators like LIKE or CHARINDEX. The only gotcha is to convert the numeric column to character -- the default conversion between character and numeric is numeric and it will cause a conversion error.
Since #Gordon, responded using LIKE, I present a solution using CHARINDEX:
SELECT *
FROM mytableTwo tb2
WHERE EXISTS (
SELECT 'x'
FROM myTable tb1
WHERE tb1.id = 23
AND CHARINDEX(CONVERT(VARCHAR(20), tb2.myfield), tb1.col1) > 0
)