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+# Entity-Relationship Diagrams - Domain Specific Language
+
+## Goals
+
+## Example
+
+### An entity User
+
+```
+CREATE ENTITY User (
+    id UUID,
+    password_hash VARCHAR(250),
+    role VARCHAR(10),
+    created_at DATETIME,
+    updated_at DATETIME
+);
+```
+
+### An entity Url
+
+```
+CREATE ENTITY Url (
+    id VARCHAR(250),
+    custom_id VARCHAR(250),
+    source_url TEXT,
+    short_url VARCHAR(250),
+    created_at DATETIME,
+    updated_at DATETIME,
+    expires_at DATETIME
+);
+```
+
+### An relationship ManageLinks
+
+```
+CREATE RELATIONSHIP ManagesLinks (
+  LINK User (0, N),
+  LINK Url (
+  HAS_ONE User,
+  HAS_MANY Url,
+  
+  <attr> <attr_type>,
+  <attr> <attr_type>,
+  <attr> <attr_type>,
+  <attr> <attr_type>,
+);
+```
+