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Display names of all constraints for a table in Oracle SQL
...CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with a lower case name (using double quotes) then the table name will be defaulted to upper ca...
ASP.NET MVC How to convert ModelState errors to json
...
You can put anything you want to inside the select clause:
var errorList = (from item in ModelState
where item.Value.Errors.Any()
select item.Value.Errors[0].ErrorMessage).ToList();
EDIT: You can extract multiple errors into separate list items by a...
How to return result of a SELECT inside a function in PostgreSQL?
... bigint
, ratio bigint) AS
$func$
BEGIN
RETURN QUERY
SELECT t.txt
, count(*) AS cnt -- column alias only visible inside
, (count(*) * 100) / _max_tokens -- I added brackets
FROM (
SELECT t.txt
FROM token t
WHERE t.charty...
Convert Newtonsoft.Json.Linq.JArray to a list of specific object type
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Just call array.ToObject<List<SelectableEnumItem>>() method. It will return what you need.
Documentation: Convert JSON to a Type
share
|
improve t...
Most efficient way to concatenate strings?
...gt; and other input types, with and without separators of different types (Char, String), but here I show the simple case of concatenating all strings in an array into a single string, with no separator. Latest version here is developed and unit-tested on C# 7 and .NET 4.7.
There are two keys to h...
Select 50 items from list at random to write to file
... leaving the original population unchanged. The resulting list is
in selection order so that all sub-slices will also be valid random
samples. This allows raffle winners (the sample) to be partitioned
into grand prize and second place winners (the subslices).
Members of the popul...
TSQL Pivot without aggregate function
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yes, but why !!??
Select CustomerID,
Min(Case DBColumnName When 'FirstName' Then Data End) FirstName,
Min(Case DBColumnName When 'MiddleName' Then Data End) MiddleName,
Min(Case DBColumnName When 'LastName' Then Data End) LastNa...
Check if a Postgres JSON array contains a string
...
As of PostgreSQL 9.4, you can use the ? operator:
select info->>'name' from rabbits where (info->'food')::jsonb ? 'carrots';
You can even index the ? query on the "food" key if you switch to the jsonb type instead:
alter table rabbits alter info type jsonb using ...
How do I use the CONCAT function in SQL Server 2008 R2?
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You can use SELECT {fn concat ('foo', 'bar')}; in previous versions. Only accepts 2 parameters though.
– Martin Smith
May 11 '12 at 11:22
...
Only read selected columns
...from the data.table-package:
You can specify the desired columns with the select parameter from fread from the data.table package. You can specify the columns with a vector of column names or column numbers.
For the example dataset:
library(data.table)
dat <- fread("data.txt", select = c("Year...