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PostgreSQL - max number of parameters in “IN” clause?
...
explain select * from test where id in (values (1), (2));
QUERY PLAN
Seq Scan on test (cost=0.00..1.38 rows=2 width=208)
Filter: (id = ANY ('{1,2}'::bigint[]))
But if try 2nd query:
explain select * from test where id = an...
Cannot ping AWS EC2 instance
...ICMP rule
Protocol: Echo Request
Port: N/A
Source: your choice (I would select Anywhere to be able to ping from any machine)
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How to send objects in NIB files to front/back?
...
Just to give a clean, up-to-date answer to this:
Select an interface object, then "Editor | Arrange | Send to back/front/etc", OR
Select the window object, then click on 'Window' above the interface editor and select the objects it contains
This pic shows where to click: ...
How does one reorder columns in a data frame?
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You can also use the subset function:
data <- subset(data, select=c(3,2,1))
You should better use the [] operator as in the other answers, but it may be useful to know that you can do a subset and a column reorder operation in a single command.
Update:
You can also use the select...
How to hide a in a menu with CSS?
...hat Chrome, it seems, will not allow me to hide <option> in a <select> . Firefox will.
13 Answers
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How to find the Number of CPU Cores via .NET/C#?
...ors:
foreach (var item in new System.Management.ManagementObjectSearcher("Select * from Win32_ComputerSystem").Get())
{
Console.WriteLine("Number Of Physical Processors: {0} ", item["NumberOfProcessors"]);
}
Cores:
int coreCount = 0;
foreach (var item in new System.Management.ManagementObjec...
Is the LIKE operator case-sensitive with MSSQL Server?
...en-us/library/ms144250(v=sql.105).aspx
(a) To check a instance collation
select serverproperty('collation')
(b) To check a database collation
select databasepropertyex('databasename', 'collation') sqlcollation
(c) To create a database using a different collation
create database exampledataba...
Adding additional data to select options using jQuery
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HTML Markup
<select id="select">
<option value="1" data-foo="dogs">this</option>
<option value="2" data-foo="cats">that</option>
<option value="3" data-foo="gerbils">other</option>
</select&...
SQL update fields of one table from fields of another one
...ic SQL is totally non-standard PostgreSQL syntax.
DO
$do$
BEGIN
EXECUTE (
SELECT
'UPDATE b
SET (' || string_agg( quote_ident(column_name), ',') || ')
= (' || string_agg('a.' || quote_ident(column_name), ',') || ')
FROM a
WHERE b.id = 123
AND a.id = b.id'
FROM i...
Postgres and Indexes on Foreign Keys and Primary Keys
...hema(s) from your program, all the information is on hand in the catalog:
select
n.nspname as "Schema"
,t.relname as "Table"
,c.relname as "Index"
from
pg_catalog.pg_class c
join pg_catalog.pg_namespace n on n.oid = c.relnamespace
join pg_catalog.pg_index ...