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CSS vertical alignment text inside li
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Define the parent with display: table and the element itself with vertical-align: middle and display: table-cell.
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How can I create a copy of an Oracle table without copying the data?
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Just use a where clause that won't select any rows:
create table xyz_new as select * from xyz where 1=0;
Limitations
The following things will not be copied to the new table:
sequences
triggers
indexes
some constraints may not be copied
materialized view logs
This also does no...
How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
...ent one-to-one, one-to-many and many-to-many relationships while designing tables with some examples?
4 Answers
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Converting string from snake_case to CamelCase in Ruby
...ring:
"AppUser".underscore # => "app_user"
or, if you want to get the table name, which is probably why you'd want the snake case:
AppUser.name.tableize # => "app_users"
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How to work around the stricter Java 8 Javadoc when using Maven
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Note that for the error no summary or caption for table, using <table summary=""> won't work anymore. If that's your situation, add a <caption> element to your table, like this:
<table>
<caption>Examples</caption>
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</table>
H...
Why were pandas merges in python faster than data.table merges in R in 2012?
...ark performs very fast in-memory merges. It's even faster than the data.table package in R (my language of choice for analysis).
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Physical vs. logical / soft delete of database record?
...and you don't have to worry about cascading a delete through various other tables in the database that reference the row you are deleting. Disadvantage is that you have to code any reporting/display methods to take the flag into account.
As far as if it is a common practice - I would say yes, but ...
Rails 3: Get Random Record
...ils 3 all examples will work. But using order RANDOM is quite slow for big tables but more sql-style
UPD. You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select max(id) from my_table) + 1
)
order by id
limit 1...
Django filter queryset __in for *every* item in list
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This would we slower if you work with large tables and large data to compare to. (like 1 Million each)
– gies0r
May 21 '18 at 16:11
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MySQL maximum memory usage
...the (f'ing) manual.
As for the database -- a few important constraints:
table engine (InnoDB, MyISAM, ...)
size
indices
usage
Most MySQL tips on stackoverflow will tell you about 5-8 so called important settings. First off, not all of them matter - e.g. allocating a lot of resources to InnoDB a...