大约有 43,000 项符合查询结果（耗时：0.0470秒） [XML]
What is this operator in MySQL?
...d <> both give UNKNOWN with NULL on either side of the expression.)
SELECT *
FROM table
WHERE YourColumn IS NOT NULL;
can also negate the null safe equality operator but this is not standard SQL.
SELECT *
FROM table
WHERE NOT (YourColumn <=> NULL);
...
Database Design for Tagging
... to rebuilt every time a question has a tag added or removed. A query like select * from question q inner join question_has_tag qt where tag_id in (select tag_id from tags where (what we want) minus select tag_id from tags where (what we don't) should be fine and scale out assuming the right b-tree ...
Jump to matching XML tags in Vim
...n do this without additional plugins:
place cursor on the tag
vat - will select the (outer) tag and place cursor on the end
once you've got your selection you can toggle between the top and bottom with o (update based on Michael Gruber's note)
c - change or, y - copy or, escape for leaving visual ...
UITableView Cell selected Color?
...f the cell other than the default [blue color] values for highlighting the selection of cell.
I use this code but nothing happens:
...
Search text in stored procedure in SQL Server
...t the schema name by adding SCHEMA_NAME(o.schema_id) AS Schema_Name to the select clause.
– patricus
Jul 7 '16 at 15:07
6
...
LINQ Using Max() to select a single row
I'm using LINQ on an IQueryable returned from NHibernate and I need to select the row with the maximum value(s) in a couple of fields.
...
Group by in LINQ
... p in persons
group p.car by p.PersonId into g
select new { PersonId = g.Key, Cars = g.ToList() };
Or as a non-query expression:
var results = persons.GroupBy(
p => p.PersonId,
p => p.car,
(key, g) => new { PersonId = key, Cars = g.ToList() });
...
Query grants for a table in postgres
...
I already found it:
SELECT grantee, privilege_type
FROM information_schema.role_table_grants
WHERE table_name='mytable'
share
|
improve this...
The multi-part identifier could not be bound
...tion is specified in the WHERE clause).
Here's an outline of your query:
SELECT
…
FROM a, b LEFT JOIN dkcd ON …
WHERE …
You are probably expecting it to behave like this:
SELECT
…
FROM (a, b) LEFT JOIN dkcd ON …
WHERE …
that is, the combination of tables a and b is joined with...
Any gotchas using unicode_literals in Python 2.6?
..., the clearer the code is, since what you want is to manipulate strings of characters, not arrays of bytes with an externally implied encoding.
– Eric O Lebigot
Sep 3 '10 at 12:35
...