Posts (page 110)
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5 min readTo load an irregular CSV file using Rust, you can use the csv crate to read and parse the file. First, you will need to add the csv crate to your Cargo.toml file: [dependencies] csv = "1.1" Next, you can use the following code to read and parse the CSV file: use std::error::Error; use std::fs::File; use std::io::prelude::*; use std::path::Path; use csv::ReaderBuilder; fn main() -> Result<(), Box<dyn Error>> { let path = Path::new("your_file.
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5 min readUsing smaller integer types in Rust can have several advantages. One major advantage is that smaller integer types like u8, u16, i8, and i16 take up less memory compared to larger integer types like u32 and u64. This can be particularly beneficial when working with large collections of integers or when memory constraints are a concern.
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4 min readWorking with vectors of strings in Rust is very similar to working with vectors of any other type. You can create a new vector of strings using the vec! macro or by using the Vec::new() constructor. Strings in Rust are represented as String objects, which are heap-allocated and mutable.To add a string to a vector, you can use the push method on the vector, like so: vec.push("some string".to_string()).
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5 min readTo convert a range to a slice in Rust, you can use the slice method provided by the standard library. This method takes the starting and ending index of the range as arguments and returns a slice that represents the elements within that range. For example, if you have a vector v and a range range, you can convert the range to a slice by calling v.slice(range.start, range.end). The resulting slice will include elements from range.start up to (but not including) range.end.
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5 min readIn Rust, a statically sized array can be created by specifying the type and size of the array using square brackets. For example, to create a statically sized array of integers with a size of 5, you can write: let arr: [i32; 5] = [1, 2, 3, 4, 5]; This declares an array named arr that can hold 5 integers of type i32. The values [1, 2, 3, 4, 5] are assigned to the array at declaration. The size of the array cannot be changed once it is defined.
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2 min readTo get column names in an Oracle SELECT statement, you can use the DESCRIBE command followed by the table name. This will display the column names, data types, and sizes of the columns in the table. Another way is to query the data dictionary views such as ALL_TAB_COLUMNS or USER_TAB_COLUMNS to retrieve information about the columns in a table. You can also use the SQL Developer tool to easily view the columns in a table by clicking on the table name and then selecting the Columns tab.
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5 min readTo copy a hyper::Request in Rust, you can simply clone the request using the .clone() method. This will create a deep copy of the request, including all headers, body and other properties. You can then use the cloned request for any further processing or modifications without affecting the original request.Here is an example of how to copy a hyper::Request: use hyper::Request; fn main() { // Create a new request let request = Request::builder() .uri("http://example.
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3 min readTo format date fields using a select query in Oracle, you can use the TO_CHAR function. This function allows you to specify the format in which you want the date to be displayed.For example, if you have a date field in your table called "order_date" and you want to display it in the format DD-MON-YYYY (e.g.
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5 min readTo remove quotes from the value of a variable in Rust, you can use the trim_matches function along with the specific character you want to remove. For example, if you want to remove quotes from a string variable named value, you can do value.trim_matches('"'). This will remove all leading and trailing double quotes from the string value.[rating:0b8e1296-57d4-4b0a-aae7-729a6718baf4]How to extract the raw value from a Rust variable by eliminating quotes.
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5 min readTo implement From<T> for Option<U> in Rust, you need to define a conversion function that takes a value of type T and returns an Option<U>. This function should be implemented on the Option<U> type and named from.
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5 min readTo connect Oracle database with Node.js, you can use the 'oracledb' module which is the official Node.js driver for Oracle Database.First, you need to install the 'oracledb' module by running the command 'npm install oracledb' in your Node.js project directory.Then, you can establish a connection to the Oracle database by providing the connection details such as user, password, host, port, and service name in the configuration object.
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4 min readIn Rust, the if return construct is allowed because of the language's design philosophy that favors explicitness and readability. This means that the Rust compiler is able to interpret and process if return statements in a way that makes sense and does not lead to ambiguity in the code. This feature allows developers to write concise and straightforward code that can help improve code readability and maintainability.