How to Construct Dynamic Queries with Conditional Where Clauses in Firestore?

Multiple Conditional Where Clauses in Firestore

This query has multiple filters, but it's inflexible because it only checks for specific author names. To create a truly dynamic filter that allows users to select multiple colors, categories, and authors, you'll need to construct the query programmatically, using conditional statements to add or skip filters as needed.

Solution

To use conditional where clauses, you'll need to:

1. Create an initial query and store it in a variable.
2. For each filter condition, use an if statement to check if the filter should be applied. If the condition is true, use query.where to add the filter to the query.
3. Repeat step 2 for all other filter conditions.
4. Finally, execute the query using query.get().

Here's an example:

var query = firebase.firestore().collection("book");

if (condition_for_color) {
    query = query.where("color", "==", "value");
}

if (condition_for_category) {
    query = query.where("category", "==", "value");
}

if (condition_for_author) {
    query = query.where("author", "==", "value");
}

if (condition_for_ordering) {
    query = query.orderBy("date");
}

query.get().then(...);

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