# Collections

In Typesense, a group of related documents is called a collection. A collection is roughly equivalent to a table in a relational database.

# Create a collection

When a collection is created, we give it a name and describe the fields that will be indexed from the documents that are added to the collection. We call this the collection's schema, which is just a fancy term to describe your documents' structure.

It might help to think of a collection "schema" as being similar to defining "types" in a strongly-typed programming language like Typescript, C, Java, Dart, Rust, etc. This ensures that the documents you add to your collection have consistent data types and are validated, and this helps prevent a whole class of errors you might typically see with mis-matched or inconsistent data types across documents.

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From Typesense v0.20, we can also create a collection that automatically detects the types of the various fields in the document.

# With pre-defined schema

Let's first create a collection with an explicit, pre-defined schema.

# Sample Response

Definition

POST ${TYPESENSE_HOST}/collections

WARNING

All fields you mention in a collection's schema will be indexed in memory.

There might be cases where you don't intend to search / filter / facet / group by a particular field and just want it to be stored (on disk) and returned as is when a document is a search hit.

You can just have these additional fields in the documents when adding them to a collection, and need not mention them in your collection schema. They will be stored on disk, and will not take up any memory.

# Field Arguments

Parameter Required Description
name yes Name of the collection you wish to create.

This can be a simple string like "name": "score".

Or you can also use a RegEx to specify field names matching a pattern. For eg: if you want to specify that all fields starting with score_ should be an integer, you can set name as "name": "score_.*".
fields yes A list of fields that you wish to index for querying, filtering and faceting. For each field, you have to specify the name and type.

Declaring a field as optional
A field can be declared as optional by setting "optional": true.

Declaring a field as a facet
A field can be declared as a facetable field by setting "facet": true.

Faceted fields are indexed verbatim without any tokenization or preprocessing. For example, if you are building a product search, color and brand could be defined as facet fields.

Declaring a field as non-indexable
You can ensure that a field is not indexed by setting "index": false. This is useful when used along with auto schema detection and you need to exclude certain fields from indexing.
default_sorting_field no The name of an int32 / float field that determines the order in which the search results are ranked when a sort_by clause is not provided during searching. This field must indicate some kind of popularity. For example, in a product search application, you could define num_reviews field as the default_sorting_field.

Additionally, when a word in a search query matches multiple possible words (either because of a typo or during a prefix search), this parameter is used to rank such equally matching tokens. For e.g. both "john" and "joan" are 1-typo away from "jofn". Similarly, in a prefix search, both "apple" and "apply" would match the prefix "app".

# Field types

Typesense allows you to index the following types of fields:

string
int32
int64
float
bool
geopoint

You can define an array or multi-valued field by suffixing a [] at the end:

string[]
int32[]
int64[]
float[]
bool[]

There are also two special field types that are used for handling data sources with varying schema via automatic schema detection.

Special Type Description
auto Automatically attempts to infer the data type based on the documents added to the collection. See automatic schema detection.
string* Automatically converts values to a string.

# With auto schema detection

While we encourage the use of a schema to ensure that you index only the fields that you need to search / filter / facet in memory, it's not always possible to know upfront what fields your documents might contain.

In such a scenario, you can define a wildcard field with the name .* and type auto to let Typesense automatically detect the type of the fields automatically. In fact, you can use any RegEx expression to define a field name.

When a .* field is defined this way, all the fields in a document are automatically indexed for searching and filtering.

WARNING

Faceting is not enabled for a wildcard field {"name": ".*" , ...}, since that can consume a lot of memory, especially for large text fields. However, you can still explicitly define specific fields (with or without RegEx names) to facet by setting facet: true for them.

For e.g. {"name": ".*_facet", "facet": true" }. This will only set field names that end with _facet in the document, as a facet.

WARNING

A geopoint field requires an explicit type definition, as the geo field value is represented as a 2-element float field and we cannot differentiate between a lat/long definition and an actual float array.

You can still define the schema for certain fields explicitly:

If an explicit definition is available for a field (country in this example), Typesense will give preference to that before falling back to the wildcard definition.

When such an explicit field definition is not available, the first document that contains a field with a given name determines the type of that field. For example, if you index a document with a field named title and it is a string, then the next document that contains the field named title will be expected to have a string too.

# Indexing all but some fields

If you have a case where you do want to index all fields in the document, except for a few fields, you can use the index: false setting to exclude fields.

For eg, if you want to index all fields, except for fields that start with description_, you can use a schema like this:

# Data Coercion

Say you've set type: auto for a particular field (or fields) (eg: popularity_score) in a collection and send the first document as:

Since popularity_score has type: auto, the data-type will automatically be set to int64 internally.

What happens when the next document's popularity_score field is not an integer field, but a string? For eg:

By default, Typesense will try to coerce (convert) the value to the previously inferred type. So in this example, since the first document had a numeric data-type for popularity_score, the second document's popularity_score field will be coerced to an integer from string.

However, this may not always work - (for eg: say the value has alphabets, it can't be coerced to an integer). In such cases, when Typesense is unable to coerce the field value to the previously inferred type, the indexing will fail with the appropriate error.

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You can control this default coercion behavior at write-time with the dirty_values parameter.

# Retrieve a collection

Retrieve the details of a collection, given its name.

# Sample Response

# Definition

GET ${TYPESENSE_HOST}/collections/:collection

# List all collections

Returns a summary of all your collections. The collections are returned sorted by creation date, with the most recent collections appearing first.

# Sample Response

# Definition

GET ${TYPESENSE_HOST}/collections

# Drop a collection

Permanently drops a collection. This action cannot be undone. For large collections, this might have an impact on read latencies.

# Sample Response

# Definition

DELETE ${TYPESENSE_HOST}/collections/:collection

Last Updated: 10/4/2021, 10:35:59 PM