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What's the difference between comma separated joins and join on syntax in MySQL? [duplicate]
...LL
)
Following query will give me all columns and rows from both tables
SELECT
*
FROM table1, table2
Following query will give me columns from first table with table alias called 'table2'
SELECT
*
FROM table1 table2
If you mistakenly forget comma in comma-separated join, second table...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...a decent programming background but my SQL experience is limited mostly to SELECT queries
– Rob
Jul 3 '12 at 14:47
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Is there a way of making strings file-path safe in c#?
...id chars and an _ for invalid ones
var validFilename = new string(filename.Select(ch => invalidFileNameChars.Contains(ch) ? '_' : ch).ToArray());
To replace invalid characters (and avoid potential name conflict like Hell* vs Hell$):
static readonly IList<char> invalidFileNameChars = Path...
Connect different Windows User in SQL Server Management Studio (2005 or later)
... use with the "runas" command.
Then, in SQL Management Studio 2005, just select the "Windows Authentication" and input the server you wanna connect to (even though the user that you can see greyed out is still the local user)... and it works!
Don't ask me why ! :)
Edit:
Make sure to include ":14...
How should I use Outlook to send code snippets?
...
If you are using Outlook 2010, you can define your own style and select your formatting you want, in the Format options there is one option for Language, here you can specify the language and specify whether you want spell checker to ignore the text with this style.
With this style you ca...
What's the @ in front of a string in C#?
...also allows multi-line contents - which can be very handy for SQL:
string select = @"
SELECT Foo
FROM Bar
WHERE Name='Baz'";
The one bit of escaping which is necessary for verbatim string literals is to get a double quote (") which you do by doubling it:
string verbatim = @"He said, ""Would you ...
Install Marketplace plugin on Eclipse Juno
... only such official distribution). However, it is available for download.
Select Help/Install new software... from the menu, select the Juno update site (http://download.eclipse.org/releases/juno), and then look for the Marketplace client - it is in the General Purpose Tools category.
...
How to choose the id generation strategy when using JPA and Hibernate
...d
uses a database-generated GUID string on MS SQL Server and MySQL.
native
selects identity, sequence or hilo depending upon the capabilities of the underlying database.
assigned
lets the application assign an identifier to the object before save() is called. This is the default strategy if no elem...
Find column whose name contains a specific string
...
# select columns containing 'spike'
df.filter(like='spike', axis=1)
You can also select by name, regular expression. Refer to: pandas.DataFrame.filter
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Reference - What does this error mean in PHP?
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mysql_fetch_array() expects parameter 1 to be resource, boolean given in select
All "mysql_fetch_array() expects parameter 1 to be resource, boolean given" Questions on Stackoverflow
Related Errors:
Warning: [function] expects parameter 1 to be resource, boolean given
Other mysql* functions ...