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Why should I capitalize my SQL keywords? [duplicate]
...nk the latter is more readable. You can easily separate the keywords from table and column names, etc.
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What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
... take up different amounts of space and they have different ranges of acceptable values.
Here are the sizes and ranges of values for SQL Server, other RDBMSes have similar documentation:
MySQL
Postgres
Oracle (they just have a NUMBER datatype really)
DB2
Turns out they all use the same specific...
Elements order in a “for (… in …)” loop
Does the "for…in" loop in Javascript loop through the hashtables/elements in the order they are declared? Is there a browser which doesn't do it in order?
The object I wish to use will be declared once and will never be modified.
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Is it a good idea to index datetime field in mysql?
.... In my application I will have many rows for example I currently have one table with 4 million records. Most of my queries use datetime clause to select data. Is it a good idea to index datetime fields in mysql database?
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Convert HTML to PDF in .NET
...use of iTextSharp for this but it does not perform well when it encounters tables and the layout just gets messy.
38 Answer...
Most efficient T-SQL way to pad a varchar on the left to a certain length?
...on cleaner, it is not very efficient in terms of execution time. The Tally table I used has 64,000 records. Kudos to Martin Smith for pointing out execution time efficiency.
SET STATISTICS TIME ON
select FORMAT(N, 'd10') as padWithZeros from Tally
SET STATISTICS TIME OFF
SQL Server Execution Tim...
How to load an ImageView by URL in Android? [closed]
...
memory twice. Bitmap memory is managed
by using a weak reference hash table,
so as soon as the image is no longer
used by you, it will be garbage
collected automatically.
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Passing an array to a query using a WHERE clause
...FROM galleries WHERE id IN (1); SELECT password FROM users;/*). Change the table & column names to something you have in your database and try that query, check out the results. You'll find a list of passwords as your result, rather than a list of galleries. Depending on how the data is output, ...
How to get record created today by rails activerecord?
...ion suggested in the accepted answer can cause performance issues when the table size grows.
Typically, if you perform lookups based on created_at column, add an index on the table in your migration file.
add_index :posts, :created_at
Now, to lookup records created today:
Rails 3/4
Post.where...
How to check if there exists a process with a given pid in Python?
...ef pid_exists(pid):
"""Check whether pid exists in the current process table.
UNIX only.
"""
if pid < 0:
return False
if pid == 0:
# According to "man 2 kill" PID 0 refers to every process
# in the process group of the calling process.
# On cert...