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How to generate a random string in Ruby
I'm currently generating an 8-character pseudo-random uppercase string for "A" .. "Z":
50 Answers
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mysql -> insert into tbl (select from another table) and some default values [duplicate]
As the title says, I am trying to insert into one table selecting values from another table and some default values.
5 Ans...
SQL join: selecting the last records in a one-to-many relationship
... want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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XML Schema minOccurs / maxOccurs default values
...ml>
<body>
<xsl:for-each select="country">
<xsl:value-of select="countryName"/><br/>
<xsl:value-of select="capital"/><br/>
<xsl:value-of select="nation...
MySQL ON vs USING?
...n tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exact same name on which they join. In this case, one may say:
SELECT ... FR...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
What is the best way to test for an empty string in Go?
...tever, since len() has to execute to completion.
– Richard
Apr 30 '18 at 11:25
Have you looked at the code generation ...
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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Is there a float input type in HTML5?
...Elfayer's edit: quotes are optional in HTML unless you want to use certain characters. Personally I prefer to omit them where possible for better readability.
– Dave
Apr 2 '14 at 10:02
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Reference alias (calculated in SELECT) in WHERE clause
The calculated value BalanceDue that is set as a variable in the list of selected columns cannot be used in the WHERE clause.
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