Design database schemas visually with tables, columns, types, indexes, and relationship lines.
Database Schema Designer provides a visual canvas for arranging database tables, defining their columns and data types, recording indexes, and drawing relationships between related structures. It is useful for inspecting how records connect without reading a long sequence of table definitions. The important distinction is that the diagram represents an intended schema. A relationship line, column type, or index shown on the canvas does not prove that a particular database engine will accept, create, or enforce that design.
A concrete input and expected output from the current implementation.
Input
Table: users Columns: id INTEGER, email TEXT Indexes: UNIQUE users_id_uq (id) Table: posts Columns: id INTEGER, user_id INTEGER Indexes: posts_user_id_idx (user_id) Relationship: posts.user_id -> users.id
Expected output
Two table boxes labeled users and posts. The users box lists id as INTEGER and email as TEXT, with the unique users_id_uq index on id. The posts box lists id and user_id as INTEGER, with posts_user_id_idx on user_id. A relationship line connects posts.user_id to users.id.
Each table, column, type, and index becomes part of the visual schema. The relationship entry supplies the connection between the referencing user_id column and the referenced id column.
Add a table for each entity, then enter its columns and select the corresponding data types. Index entries belong to the table and identify the columns covered by each index. The resulting table box keeps column definitions and index information together, making similarly named fields in different tables easier to distinguish.
Relationship lines record which part of one table refers to another table. Use the actual participating columns in the design, such as posts.user_id and users.id, rather than relying only on table proximity. The line communicates structural intent; enforcing that relationship still requires a compatible database definition outside the designer.
No. The relationship line documents the intended connection on the schema canvas. A database enforces that connection only after an appropriate foreign key or equivalent rule is defined in the database itself. Confirm that the referenced columns, types, uniqueness requirements, and engine-specific syntax are valid before implementation.
No. A visual schema can expose structural omissions, such as a missing relationship or index entry, but it does not test stored rows or execute queries against a live database. Validate the finished design with the target database engine, especially when adding uniqueness or referential constraints to populated tables.
The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.
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