diff --git a/crates/dataprof-db/src/connectors/sqlite.rs b/crates/dataprof-db/src/connectors/sqlite.rs
index 6741a3b3..289dbcd1 100644
--- a/crates/dataprof-db/src/connectors/sqlite.rs
+++ b/crates/dataprof-db/src/connectors/sqlite.rs
@@ -16,6 +16,7 @@ use async_trait::async_trait;
 use {sqlx::sqlite::SqlitePool, sqlx::sqlite::SqlitePoolOptions};
 
 /// SQLite embedded database connector
+#[derive(Debug)]
 pub struct SqliteConnector {
     #[allow(dead_code)]
     config: DatabaseConfig,
@@ -42,6 +43,30 @@ impl SqliteConnector {
             });
         }
 
+        // SQLite has no network endpoint or credentials. Reject user, password, or port.
+        // A host by itself is allowed (e.g. sqlite://relative/path.db).
+        if connection_info.username.is_some()
+            || connection_info.password.is_some()
+            || connection_info.port.is_some()
+        {
+            let mut found = Vec::new();
+            if connection_info.username.is_some() {
+                found.push("user");
+            }
+            if connection_info.password.is_some() {
+                found.push("password");
+            }
+            if connection_info.port.is_some() {
+                found.push("port");
+            }
+            let found_str = found.join(", ");
+            return Err(DataProfilerError::DatabaseConfigError {
+                message: format!(
+                    "SQLite URLs do not support {found_str}. Supported forms: sqlite:///absolute/path.db, sqlite://relative/path.db, sqlite::memory:, or a bare file path"
+                ),
+            });
+        }
+
         Ok(Self {
             config,
             connection_info,
@@ -159,8 +184,7 @@ impl DatabaseConnector for SqliteConnector {
             use sqlx::Row;
 
             let pool = self.pool.as_ref().ok_or_else(not_connected_error)?;
-
-            let query = format!("PRAGMA table_info({})", table_name);
+            let query = format!("PRAGMA table_info({table_name})");
 
             let rows = sqlx::query(&query).fetch_all(pool).await.map_err(|e| {
                 DataProfilerError::database_query(&format!("Failed to get table schema: {}", e))
@@ -188,14 +212,13 @@ impl DatabaseConnector for SqliteConnector {
             let pool = self.pool.as_ref().ok_or_else(not_connected_error)?;
 
             validate_sql_identifier(table_name)?;
-            let query = format!("SELECT COUNT(*) FROM {}", table_name);
+            let query = format!("SELECT COUNT(*) FROM {table_name}");
             let count: i64 = sqlx::query_scalar(&query)
                 .fetch_one(pool)
                 .await
                 .map_err(|e| {
                     DataProfilerError::database_query(&format!("Failed to count rows: {}", e))
                 })?;
-
             Ok(count as u64)
         }
 
@@ -207,7 +230,6 @@ impl DatabaseConnector for SqliteConnector {
         #[cfg(feature = "sqlite")]
         {
             let pool = self.pool.as_ref().ok_or_else(not_connected_error)?;
-
             let result: i32 = sqlx::query_scalar("SELECT 1")
                 .fetch_one(pool)
                 .await
@@ -231,3 +253,62 @@ impl crate::DecodeStructured for sqlx::sqlite::SqliteRow {
         None
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::DatabaseConfig;
+
+    fn config(url: &str) -> DatabaseConfig {
+        DatabaseConfig {
+            connection_string: url.to_string(),
+            ..Default::default()
+        }
+    }
+
+    #[test]
+    fn rejects_user() {
+        let err = SqliteConnector::new(config("sqlite://user@host/data.db")).unwrap_err();
+        let msg = err.to_string();
+        assert!(msg.contains("user"), "{msg}");
+        assert!(msg.contains("Supported forms"), "{msg}");
+    }
+
+    #[test]
+    fn rejects_password() {
+        let err = SqliteConnector::new(config("sqlite://:pw@host/data.db")).unwrap_err();
+        let msg = err.to_string();
+        assert!(msg.contains("password"), "{msg}");
+    }
+
+    #[test]
+    fn rejects_port() {
+        let err = SqliteConnector::new(config("sqlite://host:5432/data.db")).unwrap_err();
+        let msg = err.to_string();
+        assert!(msg.contains("port"), "{msg}");
+    }
+
+    #[test]
+    fn rejects_user_password_and_port() {
+        let err = SqliteConnector::new(config("sqlite://user:pw@host:5432/data.db")).unwrap_err();
+        let msg = err.to_string();
+        assert!(msg.contains("user"), "{msg}");
+        assert!(msg.contains("password"), "{msg}");
+        assert!(msg.contains("port"), "{msg}");
+        // Must not include the actual password.
+        assert!(!msg.contains("pw"), "{msg}");
+    }
+
+    #[test]
+    fn accepts_supported_forms() {
+        for url in [
+            "sqlite:///absolute/path.db",
+            "sqlite://relative/path.db",
+            "sqlite::memory:",
+            "/absolute/path.db",
+            "relative.db",
+        ] {
+            SqliteConnector::new(config(url)).unwrap_or_else(|e| panic!("should accept {url}: {e}"));
+        }
+    }
+}