Viewstor

PostgreSQL + Redis + ClickHouse in one extension.
Free. Open source. No paywalls.

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Why Viewstor?

Database extensions for VS Code are either locked to one database, or freemium with crippled free tiers (limited connections, no export, closed source). Switching between DBeaver and VS Code breaks flow. DataGrip costs money.

Viewstor is a free, open-source extension that covers PostgreSQL, Redis, and ClickHouse in a single tool — with features you won't find elsewhere:

	Viewstor	Database Client	SQLTools	DBCode
Price	Free forever	Freemium	Free	Freemium
Open source	AGPL-3.0	Closed (since v4.7)	MIT	Closed
PG + Redis + CH	All free	Free tier limits	No Redis	Redis/CH paid
Safe mode	Block / Warn / Off	No	No	No
Copilot Chat participant	@viewstor	No	No	No
MCP for AI agents	Built-in, free	No	No	Paid tier
Import from DBeaver/DataGrip/pgAdmin	Yes	No	No	No
Index hints	Yes	No	No	No
Color-coded folders	Nested, inherited	No	No	No

Get Started

Install from the VS Code Marketplace:

ext install Siyet.viewstor

Or search Viewstor in the Extensions panel (Ctrl+Shift+X).

Migrating from another tool?

Ctrl+Shift+P → Viewstor: Import Connections → pick your format:

• DBeaver — data-sources.json
• DataGrip — dataSources.xml
• pgAdmin — servers.json

Passwords are excluded for security — you'll enter them on first connect. See the Wiki for detailed migration guides.

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Features

Safe Mode

Production databases deserve guardrails. Safe mode runs EXPLAIN before every SELECT and catches sequential scans on large tables:

Mode	Behavior
Block	Blocks queries with Seq Scan. Shows EXPLAIN plan
Warn	Warning with "Run Anyway" / "See EXPLAIN" / "Cancel"
Off	No checks

Set globally in settings or per connection. Auto-adds LIMIT to SELECTs that don't have one.

Read-only Mode

Mark a connection or an entire folder as read-only. Child connections inherit the setting. Mutations are blocked in the query editor, result grid, and MCP commands.

Connections

• Nested folders with drag-and-drop for connections and folders
• Multi-database — list several databases in one connection, each as a separate tree node
• Color coding — theme-aware palette or hex picker, tints icons; folders pass color to children
• SSL and SSH tunnel / SOCKS5 proxy support

Schema Browser

• Tree: databases → schemas → tables, views, indexes, triggers, sequences
• Auto-collapse single-database and single-schema levels
• Hide schemas/databases from context menu
• Inaccessible objects (no permissions) rendered in error color

Query Editor

• Per-connection SQL tabs (Ctrl+Enter to execute)
• SQL autocomplete — context-aware: tables after FROM/JOIN, columns from referenced tables, table.column dot trigger, alias resolution, enum value suggestions after =/IN
• SQL diagnostics — error underline for non-existent tables, warning for unknown columns
• Index hints — warning diagnostics on WHERE/ORDER BY columns without an index
• Cancel running queries (PG: pg_cancel_backend, CH: AbortController)

Result Grid

• Server-side pagination (50 / 100 / 500 / 1000 rows)
• Estimated row count from statistics, exact count via refresh
• Inline editing with PK-based UPDATE, type-aware SQL (numeric PKs without quotes, ::jsonb cast)
• Add / delete rows — insert with DEFAULT values, delete from toolbar or right-click context menu
• Resizable columns — drag column header edge to adjust width
• Refresh button — re-run current query without page reload
• Column sorting (shift-click for multi-column)
• Cell selection with drag, Shift+Click range, resize handle
• Search with Ctrl+F, Enter to cycle matches

Export & Copy

• Export all rows (not just current page) — CSV, TSV, JSON, Markdown
• Right-click cells → Copy as CSV / TSV / Markdown / JSON
• Ctrl+C copies selected cells as TSV

Copilot Chat (@viewstor)

Ask questions about your database in natural language:

• @viewstor describe the users table
• @viewstor write a query to find orders without payments
• @viewstor what indexes are missing for this query?

Schema context is injected automatically from the active connection. Slash commands: /schema, /query, /describe. Requires GitHub Copilot.

AI Agent Integration (MCP)

Two MCP interfaces — pick the one that fits your workflow:

VS Code MCP commands (for Copilot, Cursor — agents running inside VS Code):

Command	What it does
viewstor.mcp.listConnections	List connections with status
viewstor.mcp.getSchema	Flattened schema (tables, columns, types)
viewstor.mcp.executeQuery	Run SQL (read-only enforced)
viewstor.mcp.getTableData	Fetch rows with limit
viewstor.mcp.getTableInfo	Column metadata, PKs, nullability

Standalone MCP server (for Claude Code, Cline — CLI agents running outside VS Code):

The extension installs a launcher at ~/.viewstor/mcp-server.js that auto-updates on each activation — no manual path changes needed when the extension updates.

Quick setup: Ctrl+Shift+P → Viewstor: Setup MCP → Copy Config → paste into your agent's MCP config.

Or add manually:

{
  "mcpServers": {
    "viewstor": {
      "command": "node",
      "args": ["~/.viewstor/mcp-server.js"]
    }
  }
}

7 tools: list_connections, get_schema, execute_query, get_table_data, get_table_info, add_connection, reload_connections. Reads connections from ~/.viewstor/connections.json and .vscode/viewstor.json. Connections sync bidirectionally with the VS Code extension. See the MCP Server wiki page for setup instructions.

All MCP interfaces auto-connect and respect read-only mode.

Other

• Query history with execution time and row count — click to re-execute
• DDL viewer for tables, views, indexes, triggers, sequences
• JSON/JSONB cell editor with syntax highlighting (double-click to open)
• PostgreSQL arrays displayed with {curly braces}
• Redis — inspect strings, lists, sets, sorted sets, hashes

Keyboard Shortcuts

Shortcut	Action
Ctrl+Enter / Cmd+Enter	Run query (or selected text)
Ctrl+F / Cmd+F	Search in result grid
Enter (in search)	Next match
Ctrl+C / Cmd+C	Copy selected cells
Esc	Close popups

All shortcuts use physical key codes — work on any keyboard layout.

Supported Databases

Database	Protocol	Library
PostgreSQL	TCP	pg
Redis	TCP	ioredis
ClickHouse	HTTP	@clickhouse/client

Development

Prerequisites

• Node.js 18+
• VS Code 1.93+
• Docker (for e2e tests)

Commands

npm run dev          # development build
npm run watch        # rebuild on changes
npm run build        # production build
npm run lint         # ESLint check
npm run lint:fix     # auto-fix
npm test             # unit tests (vitest)
npm run test:e2e     # e2e tests (Docker required)
npm run package      # .vsix package

Testing

Unit tests use vitest. E2E tests use testcontainers to spin up PostgreSQL, Redis, and ClickHouse in Docker. Auto-skipped if Docker is unavailable.

CI/CD

• CI (on PR, trunk push, tags): lint → unit tests → build → npm audit
• Release (on v* tag): build → test → publish to Marketplace → GitHub Release with .vsix

Contributing

See CONTRIBUTING.md.

Changelog

See CHANGELOG.md for a full list of changes per version.

License

AGPL-3.0