大约有 47,000 项符合查询结果（耗时：0.0514秒） [XML]
How to COUNT rows within EntityFramework without loading contents?
... where o.ID == '1'
from t in o.MyTable
select t).Count();
Method syntax:
var count = context.MyContainer
.Where(o => o.ID == '1')
.SelectMany(o => o.MyTable)
.Count()
Both generate the same SQL query.
...
PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
...and sequences too. Here's what I did:
Tables:
for tbl in `psql -qAt -c "select tablename from pg_tables where schemaname = 'public';" YOUR_DB` ; do psql -c "alter table \"$tbl\" owner to NEW_OWNER" YOUR_DB ; done
Sequences:
for tbl in `psql -qAt -c "select sequence_name from information_schem...
Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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How do you kill all current connections to a SQL Server 2005 database?
...problems ALTER DATABASE aspnetdb SET SINGLE_USER WITH ROLLBACK IMMEDIATE select GETDATE() ALTER DATABASE aspnetdb SET MULTI_USER what do you have instead of the commented out code?
– SQLMenace
Aug 17 '10 at 18:33
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How do I select an element with its name attribute in jQuery? [duplicate]
...
$('[name="ElementNameHere"]').doStuff();
jQuery supports CSS3 style selectors, plus some more.
See more
jQuery - Selectors
jQuery - [attribute=""] selector
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How to pick an image from gallery (SD Card) for my app?
...EQ_CODE_PICK_IMAGE:
if(resultCode == RESULT_OK){
Uri selectedImage = imageReturnedIntent.getData();
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(
selectedImage, fileP...
How to get a float result by dividing two integer values using T-SQL?
...s or parameters which are integers, you can cast them to be floats first:
SELECT CAST(1 AS float) / CAST(3 AS float)
or
SELECT CAST(MyIntField1 AS float) / CAST(MyIntField2 AS float)
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How can I get enum possible values in a MySQL database?
... This solution works on codeigniter github.com/thiswolf/codeigniter-enum-select-boxes
– You Know Nothing Jon Snow
Jul 7 '13 at 16:28
3
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Comparing date ranges
... range_start, here's some simple SQL to retrieve all the matching rows:
SELECT *
FROM periods
WHERE NOT (range_start > @check_period_end
OR range_end < @check_period_start)
Note the NOT in there. Since the two simple rules finds all the non-matching rows, a simple NOT will reve...
postgres default timezone
...
Choose a timezone from:
SELECT * FROM pg_timezone_names;
And set as below given example:
ALTER DATABASE postgres SET timezone TO 'Europe/Berlin';
Use your DB name in place of postgres in above statement.
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