import Tab from '@mdx/Tab.astro'; import Tabs from '@mdx/Tabs.astro'; import Npm from "@mdx/Npm.astro"; import Callout from '@mdx/Callout.astro'; import Steps from '@mdx/Steps.astro'; import AnchorCards from '@mdx/AnchorCards.astro'; import Breadcrumbs from '@mdx/Breadcrumbs.astro'; import CodeTabs from "@mdx/CodeTabs.astro"; import Prerequisites from "@mdx/Prerequisites.astro"; import IntrospectPostgreSQL from '@mdx/get-started/postgresql/IntrospectPostgreSQL.mdx'; import FileStructure from '@mdx/get-started/FileStructure.mdx'; import InstallPackages from '@mdx/get-started/InstallPackages.mdx'; import SetupConfig from '@mdx/get-started/SetupConfig.mdx'; import SetupEnv from '@mdx/get-started/SetupEnv.mdx'; import TransferCode from '@mdx/get-started/TransferCode.mdx'; import ApplyChanges from '@mdx/get-started/ApplyChanges.mdx'; import RunFile from '@mdx/get-started/RunFile.mdx'; import ConnectNile from '@mdx/get-started/postgresql/ConnectNile.mdx' import QueryNile from '@mdx/get-started/postgresql/QueryNile.mdx'; import QueryDatabaseUpdated from '@mdx/get-started/QueryDatabaseUpdated.mdx'; import UpdateSchema from '@mdx/get-started/postgresql/UpdateSchema.mdx'; # Get Started with Drizzle and Nile in existing project - **dotenv** - package for managing environment variables - [read here](https://www.npmjs.com/package/dotenv) - **tsx** - package for running TypeScript files - [read here](https://tsx.is/) - **Nile** - PostgreSQL re-engineered for multi-tenant apps - [read here](https://thenile.dev/) #### Step 1 - Install **postgres** package #### Step 2 - Setup connection variables #### Step 3 - Setup Drizzle config file #### Step 4 - Introspect your database Drizzle Kit provides a CLI command to introspect your database and generate a schema file with migrations. The schema file contains all the information about your database tables, columns, relations, and indices. For example, you have such table in your database: ```sql copy CREATE TABLE IF NOT EXISTS "todos" ( "id" uuid DEFAULT gen_random_uuid(), "tenant_id" uuid, "title" varchar(256), "estimate" varchar(256), "embedding" vector(3), "complete" boolean ); ``` Pull your database schema: ```bash copy npx drizzle-kit pull ``` The result of introspection will be a `schema.ts` file, `meta` folder with snapshots of your database schema, sql file with the migration and `relations.ts` file for [relational queries](/docs/rqb). Nile has several built-in tables that are part of every database. When you introspect a Nile database, the built-in tables will be included. For example, the `tenants` table that you see in the example below. This will allow you to easily create new tenants, list tenants and other operations. Here is an example of the generated `schema.ts` file: ```typescript copy filename="src/db/schema.ts" // table schema generated by introspection import { pgTable, uuid, text, timestamp, varchar, vector, boolean } from "drizzle-orm/pg-core" import { sql } from "drizzle-orm" export const tenants = pgTable("tenants", { id: uuid().default(sql`public.uuid_generate_v7()`).primaryKey().notNull(), name: text(), created: timestamp({ mode: 'string' }).default(sql`LOCALTIMESTAMP`).notNull(), updated: timestamp({ mode: 'string' }).default(sql`LOCALTIMESTAMP`).notNull(), deleted: timestamp({ mode: 'string' }), }); export const todos = pgTable("todos", { id: uuid().defaultRandom(), tenantId: uuid("tenant_id"), title: varchar({ length: 256 }), estimate: varchar({ length: 256 }), embedding: vector({ dimensions: 3 }), complete: boolean(), }); ``` Learn more about introspection in the [documentation](/docs/drizzle-kit-pull). #### Step 5 - Transfer code to your actual schema file #### Step 6 - Connect Drizzle ORM to the database #### Step 7 - Query the database #### Step 8 - Run index.ts file #### Step 9 - Update your table schema (optional) If you want to update your table schema, you can do it in the `schema.ts` file. For example, let's add a new column `deadline` to the `todos` table`: ```typescript copy filename="src/db/schema.ts" {19} import { pgTable, uuid, text, timestamp, varchar, vector, boolean } from "drizzle-orm/pg-core" import { sql } from "drizzle-orm" export const tenants = pgTable("tenants", { id: uuid().default(sql`public.uuid_generate_v7()`).primaryKey().notNull(), name: text(), created: timestamp({ mode: 'string' }).default(sql`LOCALTIMESTAMP`).notNull(), updated: timestamp({ mode: 'string' }).default(sql`LOCALTIMESTAMP`).notNull(), deleted: timestamp({ mode: 'string' }), }); export const todos = pgTable("todos", { id: uuid().defaultRandom(), tenantId: uuid("tenant_id"), title: varchar({ length: 256 }), estimate: varchar({ length: 256 }), embedding: vector({ dimensions: 3 }), complete: boolean(), deadline: timestamp({ mode: 'string' }) }); ``` #### Step 10 - Applying changes to the database (optional) #### Step 11 - Query the database with a new field (optional) If you run the `index.ts` file again, you'll be able to see the new field that you've just added. The field will be `null` since we did not populate deadlines when inserting todos previously.

nile-existing-project