clover's git

the-knife

1	---
2	title: Branches
3	description: Prisma branches group databases under git-style names — preview branches per stage, default-branch promotion, and database attachment.
4	---
5
6	A `Prisma.Branch` groups databases and apps under a git-style name
7	inside a project. Prisma tracks two separate properties:
8
9	- `role` controls whether Compute resolves `production` or `preview`
10	environment variables.
11	- `isDefault` identifies the branch new resources use when they omit
12	a branch.
13
14	The first branch created with a project has the immutable
15	`production` role. Additional branches have the `preview` role.
16	Promoting a preview branch changes `isDefault`; it does not change
17	that branch's role.
18
19	```typescript
20	import * as Prisma from "alchemy/Prisma";
21
22	const branch = yield* Prisma.Branch("preview", { project });
23	```
24
25	`gitName` is optional — omitted, alchemy generates a stable physical
26	name. Pass one when the branch should mirror a real git branch:
27
28	```typescript
29	const branch = yield* Prisma.Branch("feature", {
30	project,
31	gitName: "feature/search",
32	});
33	```
34
35	## Attaching databases
36
37	A database joins a branch by `branchId` (or `branchGitName`):
38
39	```typescript
40	const previewDb = yield* Prisma.Postgres("preview-db", {
41	project,
42	branchId: branch.branchId,
43	});
44	```
45
46	Compute apps attach the same way. Environment-variable scope follows
47	the branch's `role`, not `isDefault`, so a promoted preview branch
48	continues to use the `preview` class.
49
50	## A branch per stage
51
52	Branch names can come from the Stack's stage, giving every preview
53	stage its own branch — and the databases and apps attached to it —
54	that tears down with the stage:
55
56	```typescript
57	import { Stage } from "alchemy";
58
59	const stage = yield* Stage;
60
61	const branch = yield* Prisma.Branch("stage", {
62	project,
63	gitName: `preview/${stage}`,
64	});
65	```
66
67	## Default-branch promotion
68
69	`isDefault: true` promotes the branch, atomically clearing the current
70	default flag. The Management API only supports promotion — demotion
71	happens by promoting another branch — and alchemy records the
72	displaced branch so destroying the resource can restore it:
73
74	```typescript
75	const release = yield* Prisma.Branch("release", {
76	project,
77	gitName: "release/next",
78	isDefault: true,
79	});
80	```
81
82	The original `production`-role branch is owned by the project and
83	cannot be deleted through `Prisma.Branch`. A preview-role
84	`Prisma.Branch` promoted to default remains owned by its Branch
85	resource: on destroy, alchemy restores the displaced default and then
86	deletes the promoted branch.
87
88	## Where next
89
90	- [Postgres](/prisma/data/postgres) — projects and databases.
91	- [Connections](/prisma/data/connections) — credentials for the
92	databases on a branch.
93
94	Reference:
95
96	- [Branch API reference](/providers/prisma/branch)