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Linq code to select one item
I find myself writing a lot of code like this to select one item that matches
7 Answers
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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...
How to drop a PostgreSQL database if there are active connections to it?
...Query pg_stat_activity and get the pid values you want to kill, then issue SELECT pg_terminate_backend(pid int) to them.
PostgreSQL 9.2 and above:
SELECT pg_terminate_backend(pg_stat_activity.pid)
FROM pg_stat_activity
WHERE pg_stat_activity.datname = 'TARGET_DB' -- ← change this to your DB
AN...
How do I find a stored procedure containing ?
...
SELECT ROUTINE_NAME, ROUTINE_DEFINITION
FROM INFORMATION_SCHEMA.ROUTINES
WHERE ROUTINE_DEFINITION LIKE '%Foo%'
AND ROUTINE_TYPE='PROCEDURE'
SELECT OBJECT_NAME(id)
FROM SYSCOMMENTS
WHERE [text] LIKE...
Firefox ignores option selected=“selected”
If you change a dropdown and refresh the page, Firefox seems to ignore the selected attribute.
20 Answers
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Postgresql GROUP_CONCAT equivalent?
...
This is probably a good starting point (version 8.4+ only):
SELECT id_field, array_agg(value_field1), array_agg(value_field2)
FROM data_table
GROUP BY id_field
array_agg returns an array, but you can CAST that to text and edit as needed (see clarifications, below).
Prior to version...
In SQL, how can you “group by” in ranges?
...version.
Here are the correct versions of both of them on SQL Server 2000.
select t.range as [score range], count(*) as [number of occurences]
from (
select case
when score between 0 and 9 then ' 0- 9'
when score between 10 and 19 then '10-19'
else '20-99' end as range
from scores)...
How to make a query with group_concat in sql server [duplicate]
...
Query:
SELECT
m.maskid
, m.maskname
, m.schoolid
, s.schoolname
, maskdetail = STUFF((
SELECT ',' + md.maskdetail
FROM dbo.maskdetails md
WHERE m.maskid = md.maskid
FOR X...
How do I spool to a CSV formatted file using SQLPLUS?
...you want for numbers (avoid scientific notation on IDs)
spool myfile.csv
select table_name, tablespace_name
from all_tables
where owner = 'SYS'
and tablespace_name is not null;
Output will be like:
TABLE_PRIVILEGE_MAP ,SYSTEM
SYSTEM_PRIVILEGE_MAP...
How to import a jar in Eclipse
...o this folder all the jar files you need.
Refresh your project in eclipse.
Select all the jar files, then right click on one of them and select Build Path -> Add to Build Path
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