Fix searcing for a date on a string field.

packages/backend-core/src/sql/sql.ts

@@ -388,7 +388,7 @@ class InternalBuilder {
       }
     }
 
-    if (typeof input === "string") {
+    if (typeof input === "string" && schema.type === FieldType.DATETIME) {
       if (isInvalidISODateString(input)) {
         return null
       }

packages/server/src/api/routes/tests/search.spec.ts

@@ -1040,6 +1040,12 @@ if (descriptions.length) {
                     string: { name: "FO" },
                   }).toContainExactly([{ name: "foo" }])
                 })
+
+                it("should not coerce string to date for string columns", async () => {
+                  await expectQuery({
+                    string: { name: "2020-01-01" },
+                  }).toFindNothing()
+                })
               })
 
               describe("range", () => {