I have a query in following format, used to perform COALESCE as well as define a new column using CASE statement.
SELECT ....
COALESCE(mm1,'missing') AS mm1,
COALESCE(mm2,'missing') AS mm2,
CASE WHEN mm1='false' AND mm2='false' THEN 'No-Proxy'
WHEN mm1 IN ('false','missing') AND mm2='true' THEN 'Good-Proxy'
WHEN mm1 ='true' AND mm2 IN ('false','missing') THEN 'Bad-Proxy'
WHEN ((mm1='true' AND mm2='true') OR (mm1='missing' AND mm2='missing')
OR (mm1='false' AND mm2='missing') OR (mm1='missing' AND mm2='false')) THEN 'Unknown'
END AS Proxy_Type,
As seen above when both mm1 and mm2 are originally NULL, we need to put value as Unknown for Proxy_Type. But when we run the query, we get unexpected output. Plz see screenshot.
Kindly advise on how to fix it.
It seems that "inline/lateral column aliasing" does not allow to "override" column at the same level:
CREATE OR REPLACE TABLE t
AS SELECT NULL AS mm1, NULL AS mm2;
Option 1: Using different column alias
SELECT
COALESCE(mm1,'missing') AS mm1_,
COALESCE(mm2,'missing') AS mm2_,
CASE WHEN mm1_='false' AND mm2_='false' THEN 'No-Proxy'
WHEN mm1_ IN ('false','missing') AND mm2_='true' THEN 'Good-Proxy'
WHEN mm1_ ='true' AND mm2_ IN ('false','missing') THEN 'Bad-Proxy'
WHEN ((mm1_='true' AND mm2_='true') OR (mm1_='missing' AND mm2_='missing')
OR (mm1_='false' AND mm2_='missing')
OR (mm1_='missing' AND mm2_='false')) THEN 'Unknown'
END AS Proxy_Type
FROM t;
-- MM1_ MM2_ PROXY_TYPE
--missing missing Unknown
Option 2: LATERAL JOIN and prefixing with subquery alias:
SELECT -- t.mm1, t.mm2,
s.mm1, s.mm2,
CASE WHEN s.mm1='false' AND s.mm2='false' THEN 'No-Proxy'
WHEN s.mm1 IN ('false','missing') AND s.mm2='true' THEN 'Good-Proxy'
WHEN s.mm1 ='true' AND s.mm2 IN ('false','missing') THEN 'Bad-Proxy'
WHEN ((s.mm1='true' AND s.mm2='true') OR (s.mm1='missing' AND s.mm2='missing')
OR (s.mm1='false' AND s.mm2='missing')
OR (s.mm1='missing' AND s.mm2='false')) THEN 'Unknown'
END AS Proxy_Type
FROM t,
LATERAL(SELECT COALESCE(t.mm1,'missing') AS mm1,COALESCE(t.mm2,'missing') AS mm2) s;
-- MM1 MM2 PROXY_TYPE
--missing missing Unknown
The ideal situation would be if we had additional keyword to distinguish between original column and calculated expression, kind of SAS - calculated.
SELECT
col,
col+10 AS col,
col,
calculated col
FROM t;
-- output
t.col/expression/t.col/expression
I’m guessing you are trying to use the re-defined values of mm1/mm2 in your case statement? If so then SQL doesn’t work like that, values don’t change within the same select statement so m1/m2 will have their starting values wherever they are referenced in the select statement.
One way round this is to use something like this:
COALESCE(mm1,'missing') AS mm1,
COALESCE(mm2,'missing') AS mm2,
CASE WHEN COALESCE(mm1,'missing') ='false' …
Related
What is the easiest way to achieve the "IN" SQL functionality in Progress? Here is my code block, and I want to limit this query to 5 different pin numbers for my test. I'd rather not use a string of "OR"s if I can avoid that.
//using the "IN" way with specific pin numbers
FOR EACH names NO-LOCK WHERE names.m-date GE 1/1/1900: //AND names.pin IN (179,198,200,201,210)
FOR EACH nacminfo NO-LOCK WHERE nacminfo.pin = names.pin:
FIND FIRST nacmtype WHERE nacmtype.contact_type_num EQ nacminfo.contact_type_num
AND nacmtype.descr MATCHES ("~*" + "email") NO-LOCK NO-ERROR.
IF AVAILABLE nacmtype THEN DO:
DISPLAY
nacmtype.type_val
nacmtype.descr.
END.
END.
END.
As Stefan says, you can use LOOKUP but performance may suffer since you will need to compare every record with the list.
Using a series of OR comparisons can be very efficient and if the list is short and static (like your example) not at all hard to do.
If the list is longer or changes frequently or if it is held in a variable then you might consider iterating over the list outside the FOR EACH.
Something like this:
define variable i as integer no-undo.
define variable j as integer no-undo.
define variable n as integer no-undo.
define variable myList as character no-undo.
myList = "179,198,200,201,210".
n = num-entries( myList ).
do j = 1 to n:
FOR EACH names NO-LOCK WHERE names.m-date GE 1/1/1900 AND names.pin = entry( j, myList ):
FOR EACH nacminfo NO-LOCK WHERE nacminfo.pin = names.pin:
FIND FIRST nacmtype NO-LOCK
WHERE nacmtype.contact_type_num EQ nacminfo.contact_type_num
AND nacmtype.descr MATCHES ("~*" + "email") NO-ERROR.
IF AVAILABLE nacmtype THEN DO:
DISPLAY
nacmtype.type_val
nacmtype.descr.
END.
END.
END.
end.
Or, finally, transform the list into a temp-table. Something like this:
define temp-table tt_myList no-undo
field namePIN as character
index namePIN-idx is unique primary namePIN.
.
define variable i as integer no-undo.
define variable n as integer no-undo.
define variable myList as character no-undo.
myList = "179,198,200,201,210".
/* build a TT */
n = num-entries( myList ).
do i = 1 to n:
create tt_myList.
tt_myList.namePIN = entry( i, myList ).
end.
for each tt_myList:
FOR EACH names NO-LOCK WHERE names.m-date GE 1/1/1900 AND names.pin = tt_myList.repName:
FOR EACH nacminfo NO-LOCK WHERE nacminfo.pin = names.pin:
FIND FIRST nacmtype NO-LOCK
WHERE nacmtype.contact_type_num EQ nacminfo.contact_type_num
AND nacmtype.descr MATCHES ("~*" + "email") NO-ERROR.
IF AVAILABLE nacmtype THEN DO:
DISPLAY
nacmtype.type_val
nacmtype.descr.
END.
END.
END.
end.
You could join the TT in the FOR EACH but it won't really make any difference and, personally, I find the nested FOR EACH syntax more natural.
Do you really need that FIRST? Can there ever be more than one record in the result of that FIND?
Lastly, MATCHES isn't doing you any performance favors. Hopefully the other parts of the WHERE clause are narrowing the result set enough that its impact is minimal.
Beware of the performance, since a function on the left side generally cannot use an index, but you can use the lookup function:
for each names
where names.m-date ge 1/1/1990
and lookup( string( names.pin ), '179,198,200,201,210' ) ) > 0
no-lock:
// do something
end.
I'd rather not use a string of "OR"s if I can avoid that.
As Stefan notes, using a function in the WHERE clause means that you will not use any indexes. That will impact performance, possibly very badly.
Look into using dynamic queries to build a WHERE clause with a a bunch of OR names.pin = 179 phrases.
You will need to tweak the building of the where string to make sure that it uses the best indexes available (and that's a huge topic by itself). You can see what indexes are used via the LOG-MANAGER - see https://docs.progress.com/bundle/openedge-abl-troubleshoot-applications-122/page/Query-information-logged.html for some info on this.
define variable pins as integet extent 5 initial [179,198,200,201,210] no-undo.
define variable loop as integer no-undo.
define variable cnt as integer no-undo.
define variable whereString as character no-undo.
define query q1 for names.
whereString = ' for each names no-lock where names.m-date GE 1/1/1900'.
cnt = extent(pins).
do loop = 1 to cnt:
whereSTring = whereSTring + substitute(' OR names.pin = &1', pins[loop]).
end.
query q1:query-prepare(whereString).
query q1:query-open().
query q1:get-first().
do while available names:
// do something with the names
query q1:get-next().
end.
finally:
query q1:query-close().
end finally.
Using Oracle SQL, I want to sort the below data with values beginning with "_" followed by alphabet (without using COLLATE)
AE
BASMI1_02
CBPBC_01
_TYPERR
AE1_01
AE1_03
AEPS
AEYN
ASAS1TABLE
ASAS1_01
CBPBC_01B
CM
as
_TYPERR
AE
AE1_01
AE1_03
AEPS
AEYN
ASAS1_01
ASAS1TABLE
BASMI1_02
CBPBC_01
CBPBC_01B
CM
Try this:
select *
from table
order by case
when col like '\_%' escape '\'
then 0
else 1
end,
col;
It defines a custom sort order using case Statement
If you want the underscore values to be sorted as well then do a union separating the two, simply put:
SELECT * FROM table
WHERE col LIKE '\_%'
ORDER BY col
UNION
SELECT * FROM table
WHERE col NOT LIKE '\_%'
ORDER BY col;
I'm having trouble passing NULL as an INSERT parameter query using RPostgres and RPostgreSQL:
In PostgreSQL:
create table foo (ival int, tval text, bval bytea);
In R:
This works:
res <- dbSendQuery(con, "INSERT INTO foo VALUES($1, $2, $3)",
params=list(ival=1,
tval= 'not quite null',
bval=charToRaw('asdf')
)
)
But this throws an error:
res <- dbSendQuery(con, "INSERT INTO foo VALUES($1, $2, $3)",
params=list(ival=NULL,
tval= 'not quite null',
bval=charToRaw('asdf')
)
)
Using RPostgres, the error message is:
Error: expecting a string
Under RPostgreSQL, the error is:
Error in postgresqlExecStatement(conn, statement, ...) :
RS-DBI driver: (could not Retrieve the result : ERROR: invalid input
syntax for integer: "NULL"
)
Substituting NA would be fine with me, but it isn't a work-around - a literal 'NA' gets written to the database.
Using e.g. integer(0) gives the same "expecting a string" message.
You can use NULLIF directly in your insert statement:
res <- dbSendQuery(con, "INSERT INTO foo VALUES(NULLIF($1, 'NULL')::integer, $2, $3)",
params=list(ival=NULL,
tval= 'not quite null',
bval=charToRaw('asdf')
)
)
works with NA as well.
One option here to workaround the problem of not knowing how to articulate a NULL value in R which the PostgresSQL pacakge will be able to successfully translate is to simply not specify the column whose value you want to be NULL in the database.
So in your example you could use this:
res <- dbSendQuery(con, "INSERT INTO foo (col2, col3) VALUES($1, $2)",
params=list(tval = 'not quite null',
bval = charToRaw('asdf')
)
)
when you want col1 to have a NULL value. This of course assumes that col1 in your table is nullable, which may not be the case.
Thanks all for the help. Tim's answer is a good one, and I used it to catch the integer values. I went a different route for the rest of it, writing a function in PostgreSQL to handle most of this. It looks roughly like:
CREATE OR REPLACE FUNCTION add_stuff(ii integer, tt text, bb bytea)
RETURNS integer
AS
$$
DECLARE
bb_comp bytea;
rows integer;
BEGIN
bb_comp = convert_to('NA', 'UTF8'); -- my database is in UTF8.
-- front-end catches ii is NA; RPostgres blows up
-- trying to convert 'NA' to integer.
tt = nullif(tt, 'NA');
bb = nullif(bb, bb_comp);
INSERT INTO foo VALUES (ii, tt, bb);
GET DIAGNOSTICS rows = ROW_COUNT;
RETURN rows;
END;
$$
LANGUAGE plpgsql VOLATILE;
Now to have a look at the RPostgres source and see if there's an easy-enough way to make it handle NULL / NA a bit more easily. Hoping that it's missing because nobody thought of it, not because it's super-tricky. :)
This will give the "wrong" answer if someone is trying to put literally 'NA' into the database and mean something other than NULL / NA (e.g. NA = "North America"); given our use case, that seems very unlikely. We'll see in six months time.
How can I get a single row result (e.g. in form of a table/array) back from a sql statement. Using Lua Sqlite (LuaSQLite3). For example this one:
SELECT * FROM sqlite_master WHERE name ='myTable';
So far I note:
using "nrows"/"rows" it gives an iterator back
using "exec" it doesn't seem to give a result back(?)
Specific questions are then:
Q1 - How to get a single row (say first row) result back?
Q2 - How to get row count? (e.g. num_rows_returned = db:XXXX(sql))
In order to get a single row use the db:first_row method. Like so.
row = db:first_row("SELECT `id` FROM `table`")
print(row.id)
In order to get the row count use the SQL COUNT statement. Like so.
row = db:first_row("SELECT COUNT(`id`) AS count FROM `table`")
print(row.count)
EDIT: Ah, sorry for that. Here are some methods that should work.
You can also use db:nrows. Like so.
rows = db:nrows("SELECT `id` FROM `table`")
row = rows[1]
print(row.id)
We can also modify this to get the number of rows.
rows = db:nrows("SELECT COUNT(`id`) AS count FROM `table`")
row = rows[1]
print(row.count)
Here is a demo of getting the returned count:
> require "lsqlite3"
> db = sqlite3.open":memory:"
> db:exec "create table foo (x,y,z);"
> for x in db:urows "select count(*) from foo" do print(x) end
0
> db:exec "insert into foo values (10,11,12);"
> for x in db:urows "select count(*) from foo" do print(x) end
1
>
Just loop over the iterator you get back from the rows or whichever function you use. Except you put a break at the end, so you only iterate once.
Getting the count is all about using SQL. You compute it with the SELECT statement:
SELECT count(*) FROM ...
This will return one row containing a single value: the number of rows in the query.
This is similar to what I'm using in my project and works well for me.
local query = "SELECT content FROM playerData WHERE name = 'myTable' LIMIT 1"
local queryResultTable = {}
local queryFunction = function(userData, numberOfColumns, columnValues, columnTitles)
for i = 1, numberOfColumns do
queryResultTable[columnTitles[i]] = columnValues[i]
end
end
db:exec(query, queryFunction)
for k,v in pairs(queryResultTable) do
print(k,v)
end
You can even concatenate values into the query to place inside a generic method/function.
local query = "SELECT * FROM ZQuestionTable WHERE ConceptNumber = "..conceptNumber.." AND QuestionNumber = "..questionNumber.." LIMIT 1"
My original question
When I execute the following query in SQLite, I get this error:
Query Error: misuse of aggregate: sum() Unable to execute statement
When I change the name of the "Loan" column to something like loan_amount the error goes away and my query works fine. Why is there a problem with "Loan"?
select
t.*
, coalesce(sum(ded0.after_tax_ded_amt), 0) as "Loan"
, coalesce(sum(ded1.after_tax_ded_amt), 0) as ee_advance_amount
from totals t
left join totals as ded0
on t.ee_ssn = ded0.ee_ssn
and t.deduction_code = "Loan"
and ded0.deduction_code = "Loan"
left join totals as ded1
on t.ee_ssn = ded1.ee_ssn
and t.deduction_code = "EE Advance"
and ded1.deduction_code = "EE Advance"
group by t.ee_ssn;
Mid-post revelation
I'm pretty sure I figured out why I get the error, is it because I am comparing to "Loan" in the on-clause of my joins?
If so, how can I still use the word "Loan" for my column name in the output of my query?
I'd guess that your real problem is quote misuse. Single quotes in SQL are for quoting string literals, double quotes are for quoting column and table names that need to be case sensitive or contain odd characters. SQLite is fairly forgiving of odd syntax so it is probably making a guess about what "Loan" means and guessing incorrectly. Try this:
select
t.*
, coalesce(sum(ded0.after_tax_ded_amt), 0) as "Loan"
, coalesce(sum(ded1.after_tax_ded_amt), 0) as ee_advance_amount
from totals t
left join totals as ded0
on t.ee_ssn = ded0.ee_ssn
and t.deduction_code = 'Loan'
and ded0.deduction_code = 'Loan'
left join totals as ded1
on t.ee_ssn = ded1.ee_ssn
and t.deduction_code = 'EE Advance'
and ded1.deduction_code = 'EE Advance'
group by t.ee_ssn;