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How to make the 'cut' command treat same sequental delimiters as one?
... page:
-s, --squeeze-repeats replace each input sequence of a repeated character
that is listed in SET1 with a single occurrence
of that character
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Check if table exists in SQL Server
...nge from version to version.
To check if a table exists use:
IF (EXISTS (SELECT *
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'TheSchema'
AND TABLE_NAME = 'TheTable'))
BEGIN
--Do Stuff
END
...
Trim last character from a string
...d in this type of questions that quite everyone suggest to remove the last char of given string. But this does not fulfill the definition of Trim method.
Trim - Removes all occurrences of
white space characters from the
beginning and end of this instance.
MSDN-Trim
Under this definition ...
SQL RANK() versus ROW_NUMBER()
...he first 3 rows are tied when ordered by ID)
WITH T(StyleID, ID)
AS (SELECT 1,1 UNION ALL
SELECT 1,1 UNION ALL
SELECT 1,1 UNION ALL
SELECT 1,2)
SELECT *,
RANK() OVER(PARTITION BY StyleID ORDER BY ID) AS 'RANK',
ROW_NUMBER() OVER(PARTITION BY Style...
Fastest check if row exists in PostgreSQL
...
Use the EXISTS key word for TRUE / FALSE return:
select exists(select 1 from contact where id=12)
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How to declare a variable in MySQL?
...at has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BETWEEN @start AND @finish...
How do I map lists of nested objects with Dapper
... probably work:
Grab the courses:
var courses = cnn.Query<Course>("select * from Courses where Category = 1 Order by CreationDate");
Grab the relevant mapping:
var mappings = cnn.Query<CourseLocation>(
"select * from CourseLocations where CourseId in @Ids",
new {Ids = course...
generate days from date range
...000 days, and could be extended to go as far back or forward as you wish.
select a.Date
from (
select curdate() - INTERVAL (a.a + (10 * b.a) + (100 * c.a) + (1000 * d.a) ) DAY as Date
from (select 0 as a union all select 1 union all select 2 union all select 3 union all select 4 union all ...
JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
...
SQL select join: is it possible to prefix all columns as 'prefix.*'?
... if this is possible in SQL. Say you have two tables A and B, and you do a select on table A and join on table B:
22 Answer...