detect non-local sql tables (#1636)

Author: mbostock

src/render.ts

@@ -59,7 +59,7 @@ if (location.pathname.endsWith("/")) {
 import ${preview || page.code.length ? `{${preview ? "open, " : ""}define} from ` : ""}${JSON.stringify(
     resolveImport("observablehq:client")
   )};${
-    files.size || data?.sql
+    files.size
       ? `\nimport {registerFile${data?.sql ? ", FileAttachment" : ""}} from ${JSON.stringify(
           resolveImport("observablehq:stdlib")
         )};`

src/resolvers.ts

@@ -123,8 +123,11 @@ export async function getResolvers(
 
   // Add SQL sources.
   if (page.data.sql) {
-    for (const source of Object.values(page.data.sql)) {
-      files.add(String(source));
+    for (const value of Object.values(page.data.sql)) {
+      const source = String(value);
+      if (isAssetPath(source)) {
+        files.add(source);
+      }
     }
   }