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Can I create a One-Time-Use Function in a Script or Stored Procedure?
...s like:
create procedure #mytemp as
begin
select getdate() into #mytemptable;
end
in an SQL script, but not functions. You could have the proc store it's result in a temp table though, then use that information later in the script ..
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Applying a function to every row of a table using dplyr?
...o create an appropriately vectorised function.
R provide pmax which is suitable here, however it also provides Vectorize as a wrapper for mapply to allow you to create a vectorised arbitrary version of an arbitrary function.
library(dplyr)
# use base R pmax (vectorized in C)
iris %>% mutate(max...
In where shall I use isset() and !empty()
...nd the answer is:
$var = "";
var_dump(isset($var));
The type comparison tables in PHP’s manual is quite handy for such questions.
isset basically checks if a variable has any value other than null since non-existing variables have always the value null. empty is kind of the counter part to iss...
When to use single quotes, double quotes, and backticks in MySQL
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Backticks are to be used for table and column identifiers, but are only necessary when the identifier is a MySQL reserved keyword, or when the identifier contains whitespace characters or characters beyond a limited set (see below) It is often recommende...
How do I get the last inserted ID of a MySQL table in PHP?
I have a table into which new data is frequently inserted. I need to get the very last ID of the table. How can I do this?
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How to put more than 1000 values into an Oracle IN clause [duplicate]
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Put the values in a temporary table and then do a select where id in (select id from temptable)
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Finding duplicate values in a SQL table
...till requires all non-aggregated columns in the GROUP BY.
MySQL is unpredictable and you need sql_mode=only_full_group_by:
GROUP BY lname ORDER BY showing wrong results;
Which is the least expensive aggregate function in the absence of ANY() (see comments in accepted answer).
Oracle isn't mainstr...
How do you do a limit query in JPQL or HQL?
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// SQL: SELECT * FROM table LIMIT start, maxRows;
Query q = session.createQuery("FROM table");
q.setFirstResult(start);
q.setMaxResults(maxRows);
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How do I handle too long index names in a Ruby on Rails ActiveRecord migration?
...an unique index that gets created from the foreign keys of four associated tables:
9 Answers
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How to change height of grouped UITableView header?
I know how to change the height of the section headers in the table view. But I am unable to find any solution to change the default spacing before the first section.
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