Error for written code Current model imports certain parameters from an excel file. Hoping to allow users to override the existing values in the database through an editbox. However, I'm faced with the error (shown in attached image). The imported data is column type is in integer type, while the set function requires input of double type. I've tried placing (double) db_parameters.duration_sec and it fails too. Is there any way to replace an imported data to the data type that is required? Will not want to manually change the data type under the database fields as I may need to re-import the excel sheet from time to time which will auto reset the columns back to integer type. Thanks!
Your query should look like this:
update(db_parameters)
.where(db_parameters.tasking.eq("Receive Lot"))
.set(db_parameters.duration_sec, (int)v_ReceiveLot)
.execute();
the (int) has to be on the paremeter not on the column.
I store the following rows in my table ('DataScreen') under a JSONB column ('Results')
{"Id":11,"Product":"Google Chrome","Handle":3091,"Description":"Google Chrome"}
{"Id":111,"Product":"Microsoft Sql","Handle":3092,"Description":"Microsoft Sql"}
{"Id":22,"Product":"Microsoft OneNote","Handle":3093,"Description":"Microsoft OneNote"}
{"Id":222,"Product":"Microsoft OneDrive","Handle":3094,"Description":"Microsoft OneDrive"}
Here, In this JSON objects "Id" amd "Handle" are integer properties and other being string properties.
When I query my table like below
Select Results->>'Id' From DataScreen
order by Results->>'Id' ASC
I get the improper results because PostgreSql treats everything as a text column and hence does the ordering according to the text, and not as integer.
Hence it gives the result as
11,111,22,222
instead of
11,22,111,222.
I don't want to use explicit casting to retrieve like below
Select Results->>'Id' From DataScreen order by CAST(Results->>'Id' AS INT) ASC
because I will not be sure of the datatype of the column due to the fact that JSON structure will be dynamic and the keys and values may change next time. and Hence could happen the same with another JSON that has Integer and string keys.
I want something so that Integers in Json structure of JSONB column are treated as integers only and not as texts (string).
How do I write my query so that Id And Handle are retrieved as Integer Values and not as strings , without explicit casting?
I think your assumtions about the id field don't make sense. You said,
(a) Either id contains integers only or
(b) it contains strings and integers.
I'd say,
If (a) then numerical ordering is correct.
If (b) then lexical ordering is correct.
But if (a) for some time and then (b) then the correct order changes, too. And that doesn't make sense. Imagine:
For the current database you expect the order 11,22,111,222. Then you add a row
{"Id":"aa","Product":"Microsoft OneDrive","Handle":3095,"Description":"Microsoft OneDrive"}
and suddenly the correct order of the other rows changes to 11,111,22,222,aa. That sudden change is what bothers me.
So I would either expect a lexical ordering ab intio, or restrict my id field to integers and use explicit casting.
Every other option I can think of is just not practical. You could, for example, create a custom < and > implementation for your id field which results in 11,111,22,222,aa. ("Order all integers by numerical value and all strings by lexical order and put all integers before the strings").
But that is a lot of work (it involves a custom data type, a custom cast function and a custom operator function) and yields some counterintuitive results, e.g. 11,111,22,222,0a,1a,2a,aa (note the position of 0a and so on. They come after 222).
Hope, that helps ;)
If Id always integer you can cast it in select part and just use ORDER BY 1:
select (Results->>'Id')::int From DataScreen order by 1 ASC
Following this question I was wondering if there as in elegant way to do the same for int values.
More precisely given an Integer column with a fixed number of values (not necessarily contiguous), how would I go about mapping each number to each enum value. And when I say map I mean migrate
For example:
Lets assume the enum is as
CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy');
We would like to map:
0 -> 'sad'
1 -> 'ok'
10 -> 'happy'
Where, let's say, we have table which contains a column called mood with values {0,1,10} only.
Also, I can't see that the answer here helps me.
I use Postgres 9.5
The USING clause is an expression to tell postgresql how to transform the value. This is an expression just as you might use in SELECT. So if you need to specify a mapping then you can just use a CASE statement.
alter table foo
alter bar type mood
using
case bar
when 0 then 'sad'
when 1 then 'ok'
when 10 then 'happy'
end :: mood;
I might be doing something silly or just have a lack of understanding but I am currently working with a table of data and when I change the variable type of a column using the table.column notation when I check using the table(:,1) notation it returns a 0.
For example in my table the first column is Creditability (where table is the name of the table) so I changed the variable type using table.Creditability = logical(table.Creditability)
Then when I use islogical(table.Creditability) it returns 1
But when I use islogical(table(:,1)) it returns 0 yet when I type table(:,1) it returns a logical variable in true or false form.
I may just have a lack of understanding as I am new to this but any help would be appreciated.
Thanks
Of course it will return 0. This is because of basic point you are missing.
"table" is a structure variable in which a field named "Creditability" is created.
While "Creditability" is a logical array, it's parent "table" is still a structure.
Now, you are not getting error with statement table(:,1) although table is scalar. That is because, MATLAB treats everything as matrix. In this case, table is 1x1 matrix.
I hope it is clear now.
I am using a tFilterRow to avoid empty rows. While trying to use it I am getting only one function value 'absolute value'.
I want to filter values with a length greater than 0.
Why I am not getting any other functions?
As mentioned in the comments, the length function is only available to schema columns that have the String data type.
To filter out any rows that have a null value in a column you can use a tFilterRow but configured so that the column being checked is not equal to null like so:
In the case you are dealing with the primitive int (rather than the Integer class) then the primitive can never be null and instead defaults to 0 so you'll want to set it as not equal to 0 instead.