ERROR: `function array_position(smallint[], smallint) does not exist` while pushing schema to `postgres:9.4`

Bug description

Running prisma db push against an empty postgres:9.4 instance results in the following error message:

Prisma schema loaded from prisma/schema.prisma
Datasource "db": PostgreSQL database "tests", schema "public" at "localhost:5432"
Error: db error: ERROR: function array_position(smallint[], smallint) does not exist
HINT: No function matches the given name and argument types. You might need to add explicit type casts.
   0: sql_migration_connector::flavour::postgres::connection::describe_schema
             at migration-engine/connectors/sql-migration-connector/src/flavour/postgres/connection.rs:30
   1: migration_core::state::SchemaPush
             at migration-engine/core/src/state.rs:349

 ERROR  Command failed with exit code 1: /Users/jkomyno/Library/pnpm/store/v3/tmp/dlx-54415/node_modules/.bin/prisma db push

pnpm: Command failed with exit code 1: /Users/jkomyno/Library/pnpm/store/v3/tmp/dlx-54415/node_modules/.bin/prisma db push
    at makeError (/Users/jkomyno/.nvm/versions/node/v16.15.1/lib/node_modules/pnpm/dist/pnpx.cjs:16527:17)
    at handlePromise (/Users/jkomyno/.nvm/versions/node/v16.15.1/lib/node_modules/pnpm/dist/pnpx.cjs:17098:33)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async Object.handler [as dlx] (/Users/jkomyno/.nvm/versions/node/v16.15.1/lib/node_modules/pnpm/dist/pnpx.cjs:183480:7)
    at async /Users/jkomyno/.nvm/versions/node/v16.15.1/lib/node_modules/pnpm/dist/pnpx.cjs:192579:21
    at async run (/Users/jkomyno/.nvm/versions/node/v16.15.1/lib/node_modules/pnpm/dist/pnpx.cjs:192553:34)
    at async /Users/jkomyno/.nvm/versions/node/v16.15.1/lib/node_modules/pnpm/dist/pnpx.cjs:192625:5

Here are the logs emitted by the database:

postgres_1  | LOG:  database system is ready to accept connections
postgres_1  | ERROR:  function array_position(smallint[], smallint) does not exist at character 438
postgres_1  | HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
postgres_1  | STATEMENT:  WITH rawindex AS (
postgres_1  |       SELECT
postgres_1  |           indrelid, 
postgres_1  |           indexrelid,
postgres_1  |           indisunique,
postgres_1  |           indisprimary,
postgres_1  |           unnest(indkey) AS indkeyid,
postgres_1  |           generate_subscripts(indkey, 1) AS indkeyidx,
postgres_1  |           unnest(indclass) AS indclass,
postgres_1  |           unnest(indoption) AS indoption
postgres_1  |       FROM pg_index -- https://www.postgresql.org/docs/current/catalog-pg-index.html
postgres_1  |       WHERE
postgres_1  |           indpred IS NULL -- filter out partial indexes
postgres_1  |           AND array_position(indkey::int2[], 0::int2) IS NULL -- filter out expression indexes
postgres_1  |   )
postgres_1  |   SELECT 
postgres_1  |       indexinfo.relname AS index_name,
postgres_1  |       tableinfo.relname AS table_name,
postgres_1  |       columninfo.attname AS column_name,
postgres_1  |       rawindex.indisunique AS is_unique,
postgres_1  |       rawindex.indisprimary AS is_primary_key,
postgres_1  |       rawindex.indkeyidx AS column_index,
postgres_1  |       opclass.opcname AS opclass,
postgres_1  |       opclass.opcdefault AS opcdefault,
postgres_1  |       indexaccess.amname AS index_algo,
postgres_1  |       CASE rawindex.indoption & 1
postgres_1  |           WHEN 1 THEN 'DESC'
postgres_1  |           ELSE 'ASC' END
postgres_1  |           AS column_order
postgres_1  |   FROM
postgres_1  |       rawindex
postgres_1  |       INNER JOIN pg_class AS tableinfo ON tableinfo.oid = rawindex.indrelid
postgres_1  |       INNER JOIN pg_class AS indexinfo ON indexinfo.oid = rawindex.indexrelid
postgres_1  |       INNER JOIN pg_namespace AS schemainfo ON schemainfo.oid = tableinfo.relnamespace
postgres_1  |       INNER JOIN pg_attribute AS columninfo
postgres_1  |           ON columninfo.attrelid = tableinfo.oid AND columninfo.attnum = rawindex.indkeyid
postgres_1  |       INNER JOIN pg_am AS indexaccess ON indexaccess.oid = indexinfo.relam
postgres_1  |       LEFT JOIN pg_opclass AS opclass -- left join because crdb has no opclasses
postgres_1  |           ON opclass.oid = rawindex.indclass
postgres_1  |   WHERE schemainfo.nspname = $1
postgres_1  |   ORDER BY schemainfo.nspname, tableinfo.relname, indexinfo.relname, rawindex.indkeyidx;
postgres_1  | 

How to reproduce

Consider the following docker-compose.yml file:

# docker-compose.yml
version: '3.7'

services:
  postgres:
    image: postgres:9.4
    restart: unless-stopped
    environment:
      - POSTGRES_DB=tests
      - POSTGRES_USER=prisma
      - POSTGRES_PASSWORD=prisma
    ports:
      - '5432:5432'

• Run database: docker-compose up
• Set environment variable: export DATABASE_URL="postgres://prisma:prisma@localhost:5432/tests"
• Push schema (presented below) to database: prisma db push

Expected behavior

The schema should be pushed to the database without any error. The same schema is successfully prisma db push’d using postgres:10 to postgres:14.

Notice that array_position is mentioned in the docs of postgres:10 but not in the docs for postgres:9.

Prisma information

// ./prisma/schema.prisma
generator client {
  provider = "prisma-client-js"
}

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

model Tag {
  id Int @id
}

Environment & setup

• OS: Mac OS M1
• Database: postgres:9.4
• Node.js version: 18.8.0

Prisma Version

prisma                  : 4.3.1
@prisma/client          : 4.3.1
Current platform        : darwin-arm64
Query Engine (Node-API) : libquery-engine c875e43600dfe042452e0b868f7a48b817b9640b (at ../../../../../Library/pnpm/store/v3/tmp/dlx-54383/node_modules/.pnpm/@prisma+engines@4.3.1/node_modules/@prisma/engines/libquery_engine-darwin-arm64.dylib.node)
Migration Engine        : migration-engine-cli c875e43600dfe042452e0b868f7a48b817b9640b (at ../../../../../Library/pnpm/store/v3/tmp/dlx-54383/node_modules/.pnpm/@prisma+engines@4.3.1/node_modules/@prisma/engines/migration-engine-darwin-arm64)
Introspection Engine    : introspection-core c875e43600dfe042452e0b868f7a48b817b9640b (at ../../../../../Library/pnpm/store/v3/tmp/dlx-54383/node_modules/.pnpm/@prisma+engines@4.3.1/node_modules/@prisma/engines/introspection-engine-darwin-arm64)
Format Binary           : prisma-fmt c875e43600dfe042452e0b868f7a48b817b9640b (at ../../../../../Library/pnpm/store/v3/tmp/dlx-54383/node_modules/.pnpm/@prisma+engines@4.3.1/node_modules/@prisma/engines/prisma-fmt-darwin-arm64)
Format Wasm             : @prisma/prisma-fmt-wasm 4.3.0-32.c875e43600dfe042452e0b868f7a48b817b9640b
Default Engines Hash    : c875e43600dfe042452e0b868f7a48b817b9640b
Studio                  : 0.473.0

[Jolg42]

Note that 9.6 and older are not supported anymore by The PostgreSQL Global Development Group https://www.postgresql.org/support/versioning/

• 9.4 fails our tests
• 9.5 also fails but less, if we want to add support, we would need to investigate if we can make it supported, see current error https://github.com/prisma/prisma-engines/pull/3345

Given that we discovered this by chance and nobody reported it, what makes the most sense is to change the minimal support of PostgreSQL to 9.6 and up.

We’re happy to revisit this if people show interest in versions 9.4 or 9.5.

[Jolg42]

PostgreSQL 9.4 is unusable with Migrate / Introspection engines:

migrate dev https://github.com/prisma/prisma/actions/runs/3337373646/jobs/5523642529#step:10:731

  ● postgresql › schema only

    expect(received).resolves.toMatchInlineSnapshot()

    Received promise rejected instead of resolved
    Rejected to value: [Error: db error: ERROR: function array_position(smallint[], smallint) does not exist
    HINT: No function matches the given name and argument types. You might need to add explicit type casts.
       0: sql_migration_connector::flavour::postgres::connection::describe_schema
                 at migration-engine/connectors/sql-migration-connector/src/flavour/postgres/connection.rs:31
       1: migration_core::state::DevDiagnostic
                 at migration-engine/core/src/state.rs:251
    ]

migrate diff https://github.com/prisma/prisma/actions/runs/3337373646/jobs/5523642529#step:10:1124

  ● migrate diff › postgresql › should diff --from-url=connectionString --to-schema-datamodel=./prisma/schema.prisma --script

    expect(received).resolves.toMatchInlineSnapshot()

    Received promise rejected instead of resolved
    Rejected to value: [Error: db error: ERROR: function array_position(smallint[], smallint) does not exist
    HINT: No function matches the given name and argument types. You might need to add explicit type casts.
       0: sql_migration_connector::flavour::postgres::connection::describe_schema
                 at migration-engine/connectors/sql-migration-connector/src/flavour/postgres/connection.rs:31
    ]

db pull https://github.com/prisma/prisma/actions/runs/3337373646/jobs/5523642529#step:10:932

   ● postgresql › basic introspection

    expect(received).resolves.toMatchInlineSnapshot()

    Received promise rejected instead of resolved
    Rejected to value: [Error: Error in connector: Error querying the database: Error querying the database: Error querying the database: db error: ERROR: function array_position(smallint[], smallint) does not exist
    HINT: No function matches the given name and argument types. You might need to add explicit type casts.