Working with scalar lists
How to read, write, and filter by scalar lists / arrays
Scalar lists are represented by the [] modifier and are only available if the underlying database supports scalar lists. The following example has one scalar String list named pets:
model User {
id Int @id @default(autoincrement())
name String
pets String[]
}Example field value:
["Fido", "Snoopy", "Brian"]Setting the value of a scalar list
The following example demonstrates how to set the value of a scalar list (coinflips) when you create a model:
const createdUser = await prisma.user.create({
data: {
email: "eloise@prisma.io",
coinflips: [true, true, true, false, true],
},
});Unsetting the value of a scalar list
This method is available on MongoDB only.
The following example demonstrates how to unset the value of a scalar list (coinflips):
const createdUser = await prisma.user.create({
data: {
email: "eloise@prisma.io",
coinflips: {
unset: true,
},
},
});Unlike set: null, unset removes the list entirely.
Adding items to a scalar list
Available for PostgreSQL, CockroachDB, and MongoDB.
Use the push method to add a single value to a scalar list:
const userUpdate = await prisma.user.update({
where: {
id: 9,
},
data: {
coinflips: {
push: true,
},
},
});In earlier versions, you have to overwrite the entire value. The following example retrieves user, uses push() to add three new coin flips, and overwrites the coinflips field in an update:
const user = await prisma.user.findUnique({
where: {
email: "eloise@prisma.io",
},
});
if (user) {
console.log(user.coinflips);
user.coinflips.push(true, true, false);
const updatedUser = await prisma.user.update({
where: {
email: "eloise@prisma.io",
},
data: {
coinflips: user.coinflips,
},
});
console.log(updatedUser.coinflips);
}Filtering scalar lists
Available for PostgreSQL, CockroachDB, and MongoDB.
Use scalar list filters to filter for records with scalar lists that match a specific condition. The following example returns all posts where the tags list includes databases and typescript:
const posts = await prisma.post.findMany({
where: {
tags: {
hasEvery: ["databases", "typescript"],
},
},
});NULL values in arrays
This section applies to PostgreSQL and CockroachDB.
When using scalar list filters with a relational database connector, array fields with a NULL value are not considered by the following conditions:
NOT(array does not contain X)isEmpty(array is empty)
This means that records you might expect to see are not returned. Consider the following examples:
-
The following query returns all posts where the
tagsdo not includedatabases:const posts = await prisma.post.findMany({ where: { NOT: { tags: { has: "databases", }, }, }, });- ✔ Arrays that do not contain
"databases", such as{"typescript", "graphql"} - ✔ Empty arrays, such as
[]
The query does not return:
- ✘
NULLarrays, even though they do not contain"databases"
- ✔ Arrays that do not contain
The following query returns all posts where tags is empty:
const posts = await prisma.post.findMany({
where: {
tags: {
isEmpty: true,
},
},
});The query returns:
- ✔ Empty arrays, such as
[]
The query does not return:
- ✘
NULLarrays, even though they could be considered empty
To work around this issue, you can set the default value of array fields to [].