The use of "WHERE 1=1" in a SQL query may appear odd and largely unnecessary, but there are a few scenarios in which it can be beneficial.
Firstly, the "WHERE 1=1" clause can be used as a placeholder. This comes in handy when you need to conditionally include sections of the query depending on user inputs, but don't want to add a bunch of "IF" statements in the query. By adding "WHERE 1=1" to the beginning of the query, it allows for easier dynamic addition of conditions later in the query string.
For example, let's say you are trying to build a search query where the user can search by any combination of criteria, but not all of the criteria need to be filled out. Rather than adding a bunch of "IF" statements to the query, you could start with "WHERE 1=1" and then conditionally add other conditions as needed.
Secondly, "WHERE 1=1" can improve query performance. In certain cases, the query optimizer will ignore parts of the WHERE clause if desired columns are already indexed. By adding "WHERE 1 = 1", the optimizer is forced to evaluate the entire clause every time, since no part of it can be assumed.
In conclusion, while "WHERE 1=1" may appear to be a useless element in a SQL query, it can be quite useful in certain situations by providing a placeholder for multiple conditions and optimizing query performance.