From 2b3f76f92e9477e42533477e7ac4affdecd2d30b Mon Sep 17 00:00:00 2001
From: aayushbh-google <aayushbh@google.com>
Date: Fri, 23 Oct 2026 21:48:44 +0000
Subject: [PATCH 1/2] Minor updates to BigQuery constraints.

---
 toolbox/mdcode/docs/semantic-model/osi-google-schema.json | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/toolbox/mdcode/docs/semantic-model/osi-google-schema.json b/toolbox/mdcode/docs/semantic-model/osi-google-schema.json
index 212cb1c9..67b26f51 100644
--- a/toolbox/mdcode/docs/semantic-model/osi-google-schema.json
+++ b/toolbox/mdcode/docs/semantic-model/osi-google-schema.json
@@ -955,8 +955,9 @@
     },
     "FieldName": {
       "type": "string",
-      "pattern": "^[A-Za-z_][A-Za-z0-9_]{0,299}$",
-      "description": "A field name. A BigQuery column name: a letter or underscore, then letters, digits or underscores, up to 300 characters."
+      "pattern": "^(`[^`]+`|[\\p{L}\\p{N}\\p{Pc}\\p{Pd}\\p{M}\\s&%=>+:'<#|]+)$",
+      "maxLength": 300,
+      "description": "A field name. A BigQuery flexible column name: can be a backtick-quoted string, or contain letters, numbers, marks, connectors, dashes, spaces, and specific symbols, up to 300 characters."
     },
     "ProfileDocument": {
       "type": "object",

From 5d76123ea9736a8498e2e8b389f6bb4e595eabff Mon Sep 17 00:00:00 2001
From: aayushbh-google <aayushbh@google.com>
Date: Sat, 24 Oct 2026 01:03:29 +0000
Subject: [PATCH 2/2] adding changes to names* file along with the test case
 updates.

---
 toolbox/mdcode/src/libts/semantic/names.ts    |  6 ++--
 .../mdcode/tests/libts/semantic/names.test.ts | 32 +++++++++++++++----
 2 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/toolbox/mdcode/src/libts/semantic/names.ts b/toolbox/mdcode/src/libts/semantic/names.ts
index da25ccca..5a97a412 100644
--- a/toolbox/mdcode/src/libts/semantic/names.ts
+++ b/toolbox/mdcode/src/libts/semantic/names.ts
@@ -37,9 +37,9 @@ const IN_SQL: NameRule = {
   max: 500,
 };
 const FIELD: NameRule = {
-  pattern: /^[A-Za-z_][A-Za-z0-9_]*$/,
-  shown: '^[A-Za-z_][A-Za-z0-9_]{0,299}$',
-  says: 'a letter or underscore, then letters, digits or underscores',
+  pattern: /^(`[^`]+`|[\p{L}\p{N}\p{Pc}\p{Pd}\p{M}\s&%=>+:'<#|]+)$/u,
+  shown: "^(`[^`]+`|[\\p{L}\\p{N}\\p{Pc}\\p{Pd}\\p{M}\\s&%=>+:'<#|]+)$",
+  says: 'a BigQuery flexible column name',
   max: 300,
 };
 
diff --git a/toolbox/mdcode/tests/libts/semantic/names.test.ts b/toolbox/mdcode/tests/libts/semantic/names.test.ts
index 70d5d073..efbfca14 100644
--- a/toolbox/mdcode/tests/libts/semantic/names.test.ts
+++ b/toolbox/mdcode/tests/libts/semantic/names.test.ts
@@ -11,7 +11,9 @@ const IN_SQL: NameKind[] = ['entity', 'metric', 'relationship'];
 
 describe('nameProblem', () => {
   test('each kind accepts a plain name and rejects a slash, a leading digit or a space', () => {
-    for (const kind of KINDS) {
+    // Field names are now more flexible, so we exclude them from the restrictive tests
+    const restrictiveKinds = KINDS.filter(k => k !== 'field');
+    for (const kind of restrictiveKinds) {
       expect(nameProblem(kind, 'orders_2024')).toBeUndefined();
       for (const bad of ['sales/orders', '2024_orders', 'order date', '*', 'prod,us', '']) {
         expect(nameProblem(kind, bad)).toContain(`name '${bad}' is not valid`);
@@ -19,11 +21,28 @@ describe('nameProblem', () => {
     }
   });
 
-  test('a hyphen is accepted in a model, profile or deployment name only', () => {
+  test('a field name accepts flexible BigQuery characters, spaces, and backtick-quoting', () => {
+    // Valid unquoted flexible names
+    expect(nameProblem('field', 'order date')).toBeUndefined();
+    expect(nameProblem('field', '2024_orders')).toBeUndefined();
+    expect(nameProblem('field', 'R&D cost')).toBeUndefined();
+    expect(nameProblem('field', 'growth %')).toBeUndefined();
+
+    // Valid backtick-quoted names
+    expect(nameProblem('field', '`sales/orders!`')).toBeUndefined();
+    expect(nameProblem('field', '`my*column`')).toBeUndefined();
+
+    // Invalid unquoted names
+    for (const bad of ['sales/orders', '*', 'my@column', '']) {
+      expect(nameProblem('field', bad)).toContain(`name '${bad}' is not valid`);
+    }
+  });
+
+  test('a hyphen is accepted in a model, field, profile or deployment name only', () => {
     for (const kind of WITH_HYPHEN) {
       expect(nameProblem(kind, 'sales-analytics')).toBeUndefined();
     }
-    for (const kind of [...IN_SQL, 'field'] as NameKind[]) {
+    for (const kind of [...IN_SQL] as NameKind[]) {
       expect(nameProblem(kind, 'my-entity')).toContain(`name 'my-entity' is not valid`);
     }
   });
@@ -60,10 +79,9 @@ describe('nameProblem', () => {
     expect(nameProblem('model', 'sales/orders')).toBe(
         "Model name 'sales/orders' is not valid; names must match " +
         '^[A-Za-z][A-Za-z0-9_-]*$: a letter, then letters, digits, underscores or hyphens.');
-    expect(nameProblem('field', 'order date')).toBe(
-        "Field name 'order date' is not valid; names must match " +
-        '^[A-Za-z_][A-Za-z0-9_]{0,299}$: a letter or underscore, then letters, digits or ' +
-        'underscores.');
+    expect(nameProblem('field', 'my@column')).toBe(
+        "Field name 'my@column' is not valid; names must match " +
+        "^(`[^`]+`|[\\p{L}\\p{N}\\p{Pc}\\p{Pd}\\p{M}\\s&%=>+:'<#|]+)$: a BigQuery flexible column name.");
   });
 
   test('a catalog entry description holds 2,000 characters', () => {