大约有 44,000 项符合查询结果（耗时：0.0363秒） [XML]
PostgreSQL return result set as JSON array?
...
TL;DR
SELECT json_agg(t) FROM t
for a JSON array of objects, and
SELECT
json_build_object(
'a', json_agg(t.a),
'b', json_agg(t.b)
)
FROM t
for a JSON object of arrays.
List of objects
This section de...
Import PEM into Java Key Store
...s in the original example I found on internet:
ks.load( null, keypass.toCharArray());
ks.store( new FileOutputStream ( "mykeystore" ), keypass.toCharArray());
ks.load( new FileInputStream ( "mykeystore" ), keypass.toCharArray());
// end of section..
// read the key file from disk and create...
Android emulator-5554 offline
...ll search for ports in use starting with 565. Execute: netstat -a -n -o | Select-String ":565"
PS C:\Users\CJBS> netstat -a -n -o | Select-String ":565"
TCP 127.0.0.1:5653 127.0.0.1:5653 ESTABLISHED 5944
TCP 127.0.0.1:5657 127.0.0.1:5657 ESTABL...
How to find a table having a specific column in postgresql
...
you can query system catalogs:
select c.relname
from pg_class as c
inner join pg_attribute as a on a.attrelid = c.oid
where a.attname = <column name> and c.relkind = 'r'
sql fiddle demo
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Adding an identity to an existing column
... )
ON [PRIMARY]
go
SET IDENTITY_INSERT dbo.Tmp_Names ON
go
IF EXISTS ( SELECT *
FROM dbo.Names )
INSERT INTO dbo.Tmp_Names ( Id, Name )
SELECT Id,
Name
FROM dbo.Names TABLOCKX
go
SET IDENTITY_INSERT dbo.Tmp_Names OFF
go
DROP...
How to call a stored procedure from Java and JPA
...s (
postId IN NUMBER,
commentCount OUT NUMBER )
AS
BEGIN
SELECT COUNT(*) INTO commentCount
FROM post_comment
WHERE post_id = postId;
END;
You can call it from JPA as follows:
StoredProcedureQuery query = entityManager
.createStoredProcedureQuery("count_comments"...
How to assign a Git SHA1's to a file without Git?
...f without having Git installed. Note that "\0" is the NULL-byte, not a two-character string.
For example, the hash of an empty file:
sha1("blob 0\0") = "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391"
$ touch empty
$ git hash-object empty
e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
Another example:
sha...
IN vs OR in the SQL WHERE Clause
...h are nearly instant. When the column is not indexed I got these results:
SELECT COUNT(*) FROM t_inner WHERE val IN (1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000);
1 row fetched in 0.0032 (1.2679 seconds)
SELECT COUNT(*) FROM t_inner WHERE val = 1000 OR val = 2000 OR val = 3000 OR val = 40...
How do I perform the SQL Join equivalent in MongoDB?
...background as well, I would appreciate MongoDB taking a 'result set' (with selected returned fields) as input for a new query in one go, much like nested queries in SQL
– Stijn Sanders
Nov 26 '10 at 23:17
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HTML - Display image after selecting filename [duplicate]
I have a form that allows me with
3 Answers
3
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