Raw query failed when trying to insert batch of data

Bug description

I have a rawInsert function which is in charge of executing a raw query to insert multiple rows in a table. Function header looks like this:

export default async <T extends Record<string, any>>( table: string, fields: DistributiveKeyof<T>[], values: T[], opts?: { onConflict?: { target: (keyof T)[]; action: 'update' } }, ): Promise<number>

When I try to load test my API using k6 this function throws an error. This error happens when my batch size gets more than ~5000 rows. Error:

Raw query failed. Code: `N/A`. Message: `N/A`

How to reproduce

1. generate a query like below and execute it using executeRaw. make sure you insert more than 5000 rows in this query. INSERT INTO table_name (col1, col2, col3, col4, col5, col6) VALUES ($1, $2, $3, $4, $5, $6), ($7, $8, $9, $10, $11, $12), ...
2. run a load test over this query using k6. iterating through this also reproduces this error.
3. run the exact same query using pg driver and everything is working just fine.

Expected behavior

To have a clear error message and insert all of my batch data rows into table.

Prisma information

generator client {
  provider        = "prisma-client-js"
  previewFeatures = ["selectRelationCount"]
}

datasource db {
  provider = "postgresql"
}

Environment & setup

• OS: Mac OS
• Database: PostgreSQL
• Node.js version :v14.17.6

Prisma Version

prisma                  : 3.0.2
@prisma/client          : Not found
Current platform        : darwin
Query Engine (Node-API) : libquery-engine 2452cc6313d52b8b9a96999ac0e974d0aedf88db (at ../../.npm/_npx/52649/lib/node_modules/prisma/node_modules/@prisma/engines/libquery_engine-darwin.dylib.node)
Migration Engine        : migration-engine-cli 2452cc6313d52b8b9a96999ac0e974d0aedf88db (at ../../.npm/_npx/52649/lib/node_modules/prisma/node_modules/@prisma/engines/migration-engine-darwin)
Introspection Engine    : introspection-core 2452cc6313d52b8b9a96999ac0e974d0aedf88db (at ../../.npm/_npx/52649/lib/node_modules/prisma/node_modules/@prisma/engines/introspection-engine-darwin)
Format Binary           : prisma-fmt 2452cc6313d52b8b9a96999ac0e974d0aedf88db (at ../../.npm/_npx/52649/lib/node_modules/prisma/node_modules/@prisma/engines/prisma-fmt-darwin)
Default Engines Hash    : 2452cc6313d52b8b9a96999ac0e974d0aedf88db
Studio                  : 0.423.0

[millsp]

Internal conversation https://prisma-company.slack.com/archives/C040N0UADF0/p1662679627797069 Reproduction https://github.com/prisma/prisma/pull/15246 Todo Update snapshots once fix landed in the engines

[jkomyno]

Hi, we discovered this issue was due to a validation check in the Postgres driver we use that we didn’t expect. Specifically, even though prepared statements in Postgres support up to 65535 parameters (also known as bind variables), the driver we currently use supports half that parameters (one can create prepared SQL statements in Prisma via e.g. $executeRaw and $queryRawUnsafe). This caused us to fall back to the generic error message:

Raw query failed. Code: N/A. Message: N/A

With the latest release, prisma@4.4.0, we now show a clearer error message (with error code P2035) when the Prisma client prepares more than 32767 bind variables:

Assertion violation on the database: too many bind variables in prepared statement, expected maximum of 32767, received ...

Thus, we now consider this issue solved.

Example

Given this schema:

generator client {
  provider = "prisma-client-js"
}

datasource db {
  provider = "postgres"
  url      = env("DATABASE_URL")
}

model Tag {
  id Int @id
  @@map("tag")
}

Here’s an example of a query that fails with error code P2035 due to hitting the maximum amount of bind variables:

const n = 32768

// [1, 2, ..., 32768]
const ids = Array.from({ length }, (_, i) => i + 1)

const data = ids.map((id) => ({ id }))
await prisma.tag.createMany({
  data,
})

// ['$1', '$2', ..., '$32768']
const idsParams = ids.map((paramIdx) => `\$${paramIdx}`)

const tags = await prisma.$queryRawUnsafe<unknown[]>(
  `
  SELECT *
  FROM tag
  WHERE "id" IN (${idsParams.join(', ')})
`,
  ...ids,
)

expect(tags.length).toBe(n)

The same query with n <= 32767 succeeds.