大约有 37,000 项符合查询结果(耗时:0.0282秒) [XML]
How to avoid the “divide by zero” error in SQL?
...1 / NULLIF(CAST(NULL AS INT), 0). In real life, you are going to supply a table column to NULLIF() rather than a NULL constant. Since table columns have known datatypes, this also works fine: SELECT 1 / NULLIF(SomeNullableColumn, 0) FROM SomeTable.
– MarredCheese
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Which HTML elements can receive focus?
...ment, HTMLSelectElement, HTMLTextAreaElement and HTMLAnchorElement. This notably omits HTMLButtonElement and HTMLAreaElement.
Today's browsers define focus() on HTMLElement, but an element won't actually take focus unless it's one of:
HTMLAnchorElement/HTMLAreaElement with an href
HTMLInputElement/...
Overriding id on create in ActiveRecord
...emantics in ActiveRecord, but instead of having a migration and creating a table, and incurring the overhead of the database on every call, you just store your data in yml files. The foreign keys in the database reference the in-memory ids in the yml.
ActiveHash is great for picklists and small ta...
twig: IF with multiple conditions
... And of course I had no chance of finding that wonderful and time-saving table when looking at the IF documentation : twig.sensiolabs.org/doc/tags/if.html Thanks for the solution !
– FMaz008
Dec 5 '11 at 17:01
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What does the git index contain EXACTLY?
...ranch you just switched to.
Git 2.20 (Q4 2018) adds an Index Entry Offset Table (IEOT):
See commit 77ff112, commit 3255089, commit abb4bb8, commit c780b9c, commit 3b1d9e0, commit 371ed0d (10 Oct 2018) by Ben Peart (benpeart).
See commit 252d079 (26 Sep 2018) by Nguyễn Thái Ngọc Duy (pclouds).
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CSS fixed width in a span
... Hm, not sure. It's just a minor setback. Ended up having to use tables to get the desired effect.
– Nick Pickering
May 2 '13 at 14:10
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How to force LINQ Sum() to return 0 while source collection is empty
...uery has an additional null check and a weird outer join with a single row table.
– Maksim Vi.
Aug 11 '15 at 21:17
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How to export query result to csv in Oracle SQL Developer?
...take an export to your local system from sql developer.
Path : C:\Source_Table_Extract\des_loan_due_dtls_src_boaf.csv
SPOOL "Path where you want to save the file"
SELECT /*csv*/ * FROM TABLE_NAME;
share
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How do I kill all the processes in Mysql “show processlist”?
...<USERNAME> -p<PASSWORD>
mysqladmin processlist will print a table with the thread ids;
awk will parse from the second column only the numbers (thread ids) and generate MySQL KILL commands;
and finally the last call to mysql will execute the passed commands.
You can run grep before t...
How do I make many-to-many field optional in Django?
... blank was not as obvious to me because I thought the manytomany created a table that links the events with the groups (events = models.ManyToManyField(Event, related_name="groups", blank=True) So it was not clear to use the blank since Event is not actually a field in the group table. Anyway it wor...