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How to check which locks are held on a table
How can we check which database locks are applied on which rows against a query batch?
6 Answers
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How to create a MySQL hierarchical recursive query
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For MySQL 8+: use the recursive with syntax.
For MySQL 5.x: use inline variables, path IDs, or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
from products
where parent_id = 19
union all
se...
Does the join order matter in SQL?
Disregarding performance, will I get the same result from query A and B below? How about C and D?
4 Answers
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Select first row in each GROUP BY group?
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On Oracle 9.2+ (not 8i+ as originally stated), SQL Server 2005+, PostgreSQL 8.4+, DB2, Firebird 3.0+, Teradata, Sybase, Vertica:
WITH summary AS (
SELECT p.id,
p.customer,
p.total,
ROW_NUMBER() OVER(PARTITION BY p.c...
Rails Model find where not equal
How can I find records in my database on a not equal condition? I have this now, but is there a fancy rails-speak way of doing it?
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In which case do you use the JPA @JoinTable annotation?
In which case do you use the JPA @JoinTable annotation?
5 Answers
5
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How to get ID of the last updated row in MySQL?
How do I get the ID of the last updated row in MySQL using PHP?
12 Answers
12
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Android - Set fragment id
... I set a Fragment 's Id so that I can use getSupportFragmentManager().findFragmentById(R.id.--) ?
7 Answers
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List of lists changes reflected across sublists unexpectedly
I needed to create a list of lists in Python, so I typed the following:
14 Answers
1...
Handling a Menu Item Click Event - Android
I want to create an intent that starts a new activity once a Menu Item is clicked, but I'm not sure how to do this. I've been reading through the android documentation, but my implementation isn't correct..and some guidance in the right direction would help. I've listed my code below and commented o...