I want to split one column that is colb in the given below example into two columns
like column1 and column2.
I have a table with two columns:
Example:
create table t3
(
cola varchar,
colb varchar
);
Insertion:
insert into t3 values('D1','2021to123'),
('D2','112to24201'),
('D3','51to201');
I want to split the colb values into two columns like the following expected result:
Expected Result:
cola column1 column2
---------------------------------
D1 2021 123
D2 112 24201
D3 51 201
select cola
,split_part(colb, 'to', 1) col1
,split_part(colb, 'to', 2) col2
from t3
Quoted from the PostgreSQL Documentation:
split_part(string text, delimiter text, field int)
Split string on delimiter and return the given field (counting from
one)
Related
I have a string looks like 'ab bc 123 cd de ef 232' and I need to split this to look like :
col1
col2
col3
ab
bc
123
cd de
ef
232
Numbers have to be in the first column, the last string before the numbers has to be in the second column and all characters before that has to be in the first column.
I am working on PostreSQL and have no idea how to do that
step-by-step demo: db<>fiddle
You can use regular expressions to split your strings:
regexp_match(mystring,'^(.+)\s(.+)\s(\d+)\s(.+)\s(.+)\s(\d+)$')
(see how the RegExp works: demo: regex101)
This results in an array of strings you expect. This array can be used to fill your table:
WITH textblocks AS ( -- 1
SELECT
regexp_match(mystring,'^(.+)\s(.+)\s(\d+)\s(.+)\s(.+)\s(\d+)$') AS r
FROM mytable1
)
INSERT INTO mytable2 (col1, col2, col3)
SELECT
r[1], r[2], r[3]
FROM textblocks
UNION -- 2
SELECT
r[4], r[5], r[6]
FROM textblocks
Execute the RegExp which splits the original string into a text array
Create two records from the text array and insert it into your table
I have two queries :
Queries Simplified excluding Joins
Query 1 : select ProductName,NumberofProducts (in inventory) from Table1.....;
Query 2 : select ProductName, NumberofProductssold from Table2......;
I would like to know how I can get an output as :
ProductName NumberofProducts(in inventory) ProductName NumberofProductsSold
The relationships used for getting the outputs for each query are different.
I need the output this way for my SSRS report .
(I tried the union statement but it doesnt work for the output I want to see. )
Here is an example that does a union between two completely unrelated tables: the Student and the Products table. It generates an output that is 4 columns:
select
FirstName as Column1,
LastName as Column2,
email as Column3,
null as Column4
from
Student
union
select
ProductName as Column1,
QuantityPerUnit as Column2,
null as Column3,
UnitsInStock as Column4
from
Products
Obviously you'll tweak this for your own environment...
I think you are after something like this; (Using row_number() with CTE and performing a FULL OUTER JOIN )
Fiddle example
;with t1 as (
select col1,col2, row_number() over (order by col1) rn
from table1
),
t2 as (
select col3,col4, row_number() over (order by col3) rn
from table2
)
select col1,col2,col3,col4
from t1 full outer join t2 on t1.rn = t2.rn
Tables and data :
create table table1 (col1 int, col2 int)
create table table2 (col3 int, col4 int)
insert into table1 values
(1,2),(3,4)
insert into table2 values
(10,11),(30,40),(50,60)
Results :
| COL1 | COL2 | COL3 | COL4 |
---------------------------------
| 1 | 2 | 10 | 11 |
| 3 | 4 | 30 | 40 |
| (null) | (null) | 50 | 60 |
How about,
select
col1,
col2,
null col3,
null col4
from Table1
union all
select
null col1,
null col2,
col4 col3,
col5 col4
from Table2;
The problem is that unless your tables are related you can't determine how to join them, so you'd have to arbitrarily join them, resulting in a cartesian product:
select Table1.col1, Table1.col2, Table2.col3, Table2.col4
from Table1
cross join Table2
If you had, for example, the following data:
col1 col2
a 1
b 2
col3 col4
y 98
z 99
You would end up with the following:
col1 col2 col3 col4
a 1 y 98
a 1 z 99
b 2 y 98
b 2 z 99
Is this what you're looking for? If not, and you have some means of relating the tables, then you'd need to include that in joining the two tables together, e.g.:
select Table1.col1, Table1.col2, Table2.col3, Table2.col4
from Table1
inner join Table2
on Table1.JoiningField = Table2.JoiningField
That would pull things together for you into however the data is related, giving you your result.
If you mean that both ProductName fields are to have the same value, then:
SELECT a.ProductName,a.NumberofProducts,b.ProductName,b.NumberofProductsSold FROM Table1 a, Table2 b WHERE a.ProductName=b.ProductName;
Or, if you want the ProductName column to be displayed only once,
SELECT a.ProductName,a.NumberofProducts,b.NumberofProductsSold FROM Table1 a, Table2 b WHERE a.ProductName=b.ProductName;
Otherwise,if any row of Table1 can be associated with any row from Table2 (even though I really wonder why anyone'd want to do that), you could give this a look.
Old question, but where others use JOIN to combine unrelated queries to rows in one table, this is my solution to combine unrelated queries to one row, e.g:
select
(select count(*) c from v$session where program = 'w3wp.exe') w3wp,
(select count(*) c from v$session) total,
sysdate
from dual;
which gives the following one-row output:
W3WP TOTAL SYSDATE
----- ----- -------------------
14 290 2020/02/18 10:45:07
(which tells me that our web server currently uses 14 Oracle sessions out of the total of 290 sessions; I log this output without headers in an sqlplus script that runs every so many minutes)
Load each query into a datatable:
http://www.dotnetcurry.com/ShowArticle.aspx?ID=143
load both datatables into the dataset:
http://msdn.microsoft.com/en-us/library/aeskbwf7%28v=vs.80%29.aspx
This is what you can do. Assuming that your ProductName column have common values.
SELECT
Table1.ProductName,
Table1.NumberofProducts,
Table2.ProductName,
Table2.NumberofProductssold
FROM Table1
INNER JOIN Table2
ON Table1.ProductName= Table2.ProductName
Try this:
SELECT ProductName,NumberofProducts ,NumberofProductssold
FROM table1
JOIN table2
ON table1.ProductName = table2.ProductName
Try this:
GET THE RECORD FOR CURRENT_MONTH, LAST_MONTH AND ALL_TIME AND MERGE THEM INTO SINGLE ARRAY
$analyticsData = $this->user->getMemberInfoCurrentMonth($userId);
$analyticsData1 = $this->user->getMemberInfoLastMonth($userId);
$analyticsData2 = $this->user->getMemberInfAllTime($userId);
foreach ($analyticsData2 as $arr) {
foreach ($analyticsData1 as $arr1) {
if ($arr->fullname == $arr1->fullname) {
$arr->last_send_count = $arr1->last_send_count;
break;
}else{
$arr->last_send_count = 0;
}
}
foreach ($analyticsData as $arr2) {
if ($arr->fullname == $arr2->fullname) {
$arr->current_send_count = $arr2->current_send_count;
break;
}else{
$arr->current_send_count = 0;
}
}
}
echo "<pre>";
print_r($analyticsData2);die;
[beginner]
I have a table that looks like this:
colA colB
1 <null>
2 <null>
3 <null>
colB is the new empty column I added to the table. colA is varchar and colB is double precision data type (float).
I want to update colB with a colA multiplied by 2.
New table should look like this:
colA colB
1 2
2 4
3 6
When I go to update colB like so:
update tablename set colB = colA * 2
I get error:
Invalid operation: Invalid input syntax for type numeric
Ive tried to work around this with solutions like this:
update tablename set colB = COALESCE(colA::numeric::text,'') * 2
but get the same error.
In a select statement on the same table, this works on colA which is varchar:
select colA * 2 from tablename
How can I update a column with mathematical operations with different datatype reference columns? I cant update datatype for colA.
I suppose that Laurenz Albe is correct and there are non-numeric values in col_a
So UPDATE must be guarded:
UPDATE T
SET col_b =
CASE
WHEN col_a ~'^([0-9]+\.?[0-9]*|\.[0-9]+)$' THEN col_a::numeric *2
END ;
-- or this way
UPDATE T
SET col_b = col_a::numeric *2
WHERE
col_a ~'^([0-9]+\.?[0-9]*|\.[0-9]+)$' ;
Look at fiddle: https://www.db-fiddle.com/f/4wFynf9WiEuiE499XMcsCT/1
Recipes for "isnumeric" you can get here: isnumeric() with PostgreSQL
There is a value in the string column that is not a valid number. You will have to fix the data or exclude certain rows with a WHERE condition.
If you say that running the query from your client works, that leads me to suspect that your client doesn't actually execute the whole query, but slaps a LIMIT on it (some client tools do that).
The following query will have to process all rows and should fail:
SELECT colA * 2 AS double
FROM tablename
ORDER BY double;
update tablename set colB = colA::numeric * 2
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 would like to create a view and I do some data handling for each result of unnest function.
In my column column2 I have :
"12345"
"123456"
"12345,123456" or more number
I would like to do some unnest(col2, ',') and for each result do something like this:
if length(col2) = 5 then treatment_1
else if length(col2) = 6 then treatment_2
Example in table:
col1 col2
-------------------
D1 12345, 123456
D3 12345
D4 123456
Expected Result into a view (with a treatment for each row in a col2) :
col1 col2
-------------------
D1 12345
D1 123456
D3 12345
D4 123456
You can use regexp_split_to_table to split the string into multiple rows:
select t1.col1
, case
when length(split.col2) > 5 then right(split.col2, 3)
else replace(split.col2, '123', '***')
end as col2
from Table1 t1
cross join
regexp_split_to_table(t1.col2, '\s*,\s*') split(col2)
Working example at SQL Fiddle.