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How can I disable the UITableView selection?
When you tap a row in a UITableView , the row is highlighted and selected. Is it possible to disable this so tapping a row does nothing?
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What are the options for storing hierarchical data in a relational database? [closed]
...useful for managing hierarchical data:
the HierarchyId data type.
common table expressions, using the with keyword.
Have a look at "Model Your Data Hierarchies With SQL Server 2008" by Kent Tegels on MSDN for starts. See also my own question: Recursive same-table query in SQL Server 2008
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Rails Model find where not equal
...User.where.not(user_id: me)
In Rails 3.x
GroupUser.where(GroupUser.arel_table[:user_id].not_eq(me))
To shorten the length, you could store GroupUser.arel_table in a variable or if using inside the model GroupUser itself e.g., in a scope, you can use arel_table[:user_id] instead of GroupUser.are...
Warning: Null value is eliminated by an aggregate or other SET operation in Aqua Data Studio
... solve this problem?. How to change the null data to 0 when no data in the table?.
6 Answers
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Spring @Transactional - isolation, propagation
...tted: Allows dirty reads.
Read Committed: Does not allow dirty reads.
Repeatable Read: If a row is read twice in the same transaction, the result will always be the same.
Serializable: Performs all transactions in a sequence.
The different levels have different performance characteristics in a mul...
Laravel Eloquent Sum of relation's column
... is no price column. It looks like eloquent is not looking at that Product table at all....
– theAdmiral
Feb 10 '14 at 15:22
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Delete all Duplicate Rows except for One in MySQL? [duplicate]
How would I delete all duplicate data from a MySQL Table?
2 Answers
2
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Opposite of %in%: exclude rows with values specified in a vector
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If you look at the code of %in%
function (x, table) match(x, table, nomatch = 0L) > 0L
then you should be able to write your version of opposite. I use
`%not in%` <- function (x, table) is.na(match(x, table, nomatch=NA_integer_))
Another way is:
function (x,...
MySQL skip first 10 results
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There is an OFFSET as well that should do the trick:
SELECT column FROM table
LIMIT 10 OFFSET 10
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How can I select rows with most recent timestamp for each key value?
I have a table of sensor data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some of the other fields.
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