Typeorm "OR" operator

Multiple conditions using "OR" operator

In the arena of TypeORM, you occasionally step into the ring with tougher and complex adversaries. Let’s arm our OR operator with additional deftness.

Mashing up "OR" with "AND"

When your application demands joining both OR and AND conditions, TypeORM's got your back! By nesting objects inside the where array, you can construct complex queries:

const users = await userRepository.find({
    where: [
        { 
            firstName: 'Alice', 
            lastName: 'Smith' 
        },
        { 
            firstName: 'Bob',
            age: LessThan(30) 
        }
    ]
});


This gives you users either named "Alice Smith" or named "Bob" who are under 30. So, it's an All-Star game rather than a one-man show.

Dynamic "OR" conditions through parameters

When your logic calls for swinging with dynamic values, call the cavalry - use the find option and pass parameters:

const userConditions = [
    { firstName: 'Alice' },
    { lastName: 'Smith' }
];
// Let's say userConditions are populated based on some voodoo logic
const users = await userRepository.find({ where: userConditions });


This tactic puts you in the driver seat dictating and manipulating conditions dynamically.

Complex "OR" operations using QueryBuilder

If your ambitions outgrow simple conditions, it's time to suit up with QueryBuilder for phenomenal cosmic power. Here is a mighty example:

const users = await userRepository
    .createQueryBuilder("user")
    .where("user.firstName = :firstName", { firstName: "Alice" })
    .orWhere("user.lastName = :lastName", { lastName: "Smith" })
    .getMany();


QueryBuilder beckons you wield the power of more precise and extensive query building.

Expanding horizons

Conduct "OR" operations without over-reliance on QueryBuilder

While QueryBuilder is a powerful tool in your arsenal, don't feel obligated to use it for every "OR" condition. The simple and efficient find method with array syntax is also an effective weapon for handling OR operations.

Ensuring accuracy in defining conditions

Ensure to deploy the conditions in their precise places as TypeORM merges conditions using AND within a single object and OR when conditions are in separate objects. Any misplacement of conditions can lead to a faulty command with unintended results. So, no room for hide and seek here!

Performance implications with extensive "OR" usage

Should you opt to star the 'OR' operator in most of your queries, be warned of possible slower query execution. Indexing commonly used columns as a counter-measure can be a significant boost to performance. Keep a keen eye out on query performance and adjust accordingly.