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6 min readTo remove duplicate records in an Oracle query, you can use the DISTINCT keyword in your SELECT statement. This keyword eliminates duplicate rows from the result set based on all selected columns. Alternatively, you can use the ROW_NUMBER() analytical function to assign a unique row number to each row and then filter out duplicate rows by selecting only the rows with row numbers equal to 1.
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5 min readTo match a string against patterns in Oracle SQL, you can use the LIKE operator along with wildcard characters. The percent sign % represents zero or more characters, while the underscore _ represents a single character. For example, to find all values that start with 'ABC', you can use WHERE column_name LIKE 'ABC%'.Another option in Oracle SQL is to use regular expressions with the REGEXP_LIKE function.
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5 min readTo access memory-mapped registers in Rust, you first need to create a struct that represents the memory-mapped register block. This struct should have fields that correspond to the registers within the block. You can use the volatile crate to ensure that read and write operations on the registers are not optimized out by the compiler.Next, you need to define functions or methods on the struct that read from and write to the registers.
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6 min readTo get a user from a db_link using Oracle, you can use the following SQL query:SELECT * FROM user@db_link_name;Replace "user" with the name of the user you want to retrieve and "db_link_name" with the name of the database link established in your Oracle database. This query will allow you to retrieve the user information from the linked database. Make sure the necessary permissions and configurations are in place to access the remote database through the database link.
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6 min readTo create an iterable trait for references in Rust, you can define a trait with a method that returns an iterator over the reference type. This iterator should provide access to the inner data through methods like next() and into_iter().You can also implement the IntoIterator trait for your reference type, which allows you to convert references into iterators directly using the into_iter() method.
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4 min readTo remove a single quote from a string in Oracle, you can use the REPLACE function. You can do this by using the following syntax: SELECT REPLACE(your_column_name, '''', '') FROM your_table_name; In this syntax, your_column_name is the name of the column from which you want to remove the single quote, and your_table_name is the name of the table where the column is located.
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5 min readTo fake a connection refused in Rust, you can create a mock server that intentionally rejects incoming connections. This can be achieved by writing a simple TCP server using a library like tokio or async-std and configuring it to reject incoming connections. You can set up the server to immediately close the connection or return an error response when a connection attempt is made.
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4 min readTo create an auto increment in Oracle 11g, you can use a sequence object.First, create a sequence using the following syntax: CREATE SEQUENCE sequence_name START WITH 1 INCREMENT BY 1 NOCACHE;Next, create a trigger on the table where you want the auto increment to occur. This trigger will automatically insert the next value from the sequence into the specified column of the table.
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5 min readTo clone a database table with constraints in Oracle, you can use the CREATE TABLE AS SELECT statement. This statement creates a new table based on the result set of a SELECT query from the original table.You can include constraints in the new table by including them in the SELECT statement or by creating them separately using the ALTER TABLE statement after the new table is created.
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4 min readIn Rust, a recursive trait bound is a way to define a trait that requires a type parameter to implement the trait itself. This can be useful in situations where a trait defines methods that return or take as arguments the implementing type.To define a recursive trait bound in Rust, you simply reference the trait itself within its own definition.
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4 min readTo implement an abstract factory in Rust, you can start by defining a trait that represents the abstract factory. This trait will declare the methods that will be implemented by concrete factories. Next, create concrete factory structs that implement the trait and provide the necessary methods.Inside the concrete factory structs, you can define methods that create specific types of products.