Prisma · Const

contains

contains is a Prisma Client string filter that matches records whose selected field includes a specified substring. Combine it with mode: "insensitive" for case-insensitive matching.

How it works

Use contains inside a string field's where filter to select records whose value includes a specified substring. Add mode: "insensitive" when the query should ignore letter casing, as shown in the Prisma Client reference example.

Syntax

{ field: { contains: string, mode?: "default" | "insensitive" } }

Parameters

Name	Type	Description
`contains`	`string`	Substring to search for in the selected string field.
`mode`	`QueryMode`	Controls case sensitivity; use `insensitive` for case-insensitive matching.

Returns

A filtered Prisma Client query result containing records whose selected string field includes the requested substring.

Key points

contains is one of Prisma Client's string filter operators, alongside operators such as startsWith.
The reference documents a query that filters records by a title containing a substring while ignoring case.
String filters are applied through Prisma Client's where query option.
A contains condition can participate in compound filtering with Prisma's logical operators.

Common mistakes

Case-insensitive matching requires the mode: "insensitive" option; contains alone does not request case-insensitive behavior.

Example: Case-insensitive substring filter

const posts = await prisma.post.findMany({
  where: {
    title: {
      contains: "Prisma",
      mode: "insensitive",
    },
  },
});

Returns posts whose title contains “Prisma”, ignoring letter case.

When to use it

Substring search

Search posts by title or other text fields for a user-provided term.

Case-insensitive search

Match text regardless of capitalization, such as names or titles entered inconsistently.

Combined filtering

Use a text condition together with other field predicates in a compound where clause.

Interview questions

QWhat does the contains filter do?

contains is a Prisma Client string filter used inside a field condition in where. It matches records whose field value includes the supplied substring.

Follow-up: How would you make the match case-insensitive? Add mode: "insensitive" alongside contains in the same field filter.

QHow is contains written in a Prisma Client query?

Place contains in the string field's filter object, for example title: { contains: "Prisma" }. The surrounding query can be a normal Prisma Client operation such as findMany.

Follow-up: How can the filter be combined with another condition? Add another field condition or compose conditions with Prisma's logical operators such as AND or OR.

QHow do you perform a case-insensitive contains query?

The documented example combines contains: "Prisma" with mode: "insensitive" to match the substring without regard to case. This is useful when users may enter different capitalization.

Follow-up: What broader query feature contains this operator? Prisma Client filtering uses the where option, which supports multiple field conditions and logical operators.

startsWith
endsWith
where
OR
AND
NOT

Source: Prisma Client API. Checked 2026-10-16.