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running Rails console in production
I have just gone live with my first Rails site, but now I have a problem. When I run the project in development mode on my IDE I can run the console to something like:
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DROP IF EXISTS VS DROP?
... TABLE table_name;
IF EXISTS is not standard; different platforms might support it with different syntax, or not support it at all. In PostgreSQL, the syntax is
DROP TABLE IF EXISTS table_name;
The first one will throw an error if the table doesn't exist, or if other database objects depend on ...
How to prepend a string to a column value in MySQL?
I need a SQL update statement for updating a particular field of all the rows with a string "test" to be added in the front of the existing value.
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Size of font in CSS with slash
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This actually sets two properties and is equivalent to:
font-size: 100%;
line-height: 120%;
To quote the official documentation:
The syntax of this property is based on a traditional typographical shorthand notation to set mul...
Are nullable types reference types?
When I declare an int as nullable
6 Answers
6
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Java: PrintStream to String?
I have a function that takes an object of a certain type, and a PrintStream to which to print, and outputs a representation of that object. How can I capture this function's output in a String? Specifically, I want to use it as in a toString method.
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Switch to another Git tag
How do I check out version version/tag 1.1.4 of the rspec bundle ?
2 Answers
2
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What is the difference between Class.this and this in Java
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In this case, they are the same. The Class.this syntax is useful when you have a non-static nested class that needs to refer to its outer class's instance.
class Person{
String name;
public void setName(String name){
this.name = name;
}
class Displayer {
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Numpy how to iterate over columns of array?
Suppose I have and m x n array. I want to pass each column of this array to a function to perform some operation on the entire column. How do I iterate over the columns of the array?
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