大约有 12,000 项符合查询结果（耗时：0.0124秒） [XML]
How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...dn't want the overhead of a function. I came up with the following query:
SELECT myfield::integer FROM mytable WHERE myfield ~ E'^\\d+$';
Postgres shortcuts its conditionals, so you shouldn't get any non-integers hitting your ::integer cast. It also handles NULL values (they won't match the regex...
SQL Server 2008: How to query all databases sizes?
...
with fs
as
(
select database_id, type, size * 8.0 / 1024 size
from sys.master_files
)
select
name,
(select sum(size) from fs where type = 0 and fs.database_id = db.database_id) DataFileSizeMB,
(select sum(size) from fs wh...
MySQL selecting yesterday's date
...get yesterday's date is:
subdate(current_date, 1)
Your query would be:
SELECT
url as LINK,
count(*) as timesExisted,
sum(DateVisited between UNIX_TIMESTAMP(subdate(current_date, 1)) and
UNIX_TIMESTAMP(current_date)) as timesVisitedYesterday
FROM mytable
GROUP BY 1
For the ...
is it possible to select EXISTS directly as a bit?
...workaround.
If you must return a conditional bit 0/1 another way is to:
SELECT CAST(
CASE WHEN EXISTS(SELECT * FROM theTable where theColumn like 'theValue%') THEN 1
ELSE 0
END
AS BIT)
Or without the cast:
SELECT
CASE
WHEN EXISTS( SELECT 1 FROM theTable WHERE theColumn LI...
Adding a public key to ~/.ssh/authorized_keys does not log me in automatically
...
fixed the problem for me on 1and1 (1und1) server
– musicman
Dec 10 '17 at 14:18
add a comment
|
...
Best approach to remove time part of datetime in SQL Server
...
Strictly, method a is the least resource intensive:
a) select DATEADD(dd, DATEDIFF(dd, 0, getdate()), 0)
Proven less CPU intensive for same total duration a million rows by some one with way too much time on their hands: Most efficient way in SQL Server to get date from date+ti...
How to round an average to 2 decimal places in PostgreSQL?
... round that takes a precision is only available for numeric.
regress=> SELECT round( float8 '3.1415927', 2 );
ERROR: function round(double precision, integer) does not exist
regress=> \df *round*
List of functions
Schema | Name | Result data type | Argument...
Imply bit with constant 1 or 0 in SQL Server
Is it possible to express 1 or 0 as a bit when used as a field value in a select statement?
8 Answers
...
Remove Object from Array using JavaScript
...e no elements in the array that match the condition findIndex will return -1and putting this directly into splice will result in an arbitraty deletion of the last element in the array.
– jdnz
Feb 19 at 10:06
...
How do I use the CONCAT function in SQL Server 2008 R2?
...
You can use SELECT {fn concat ('foo', 'bar')}; in previous versions. Only accepts 2 parameters though.
– Martin Smith
May 11 '12 at 11:22
...