diff --git a/alembic/pfsa-db01-gb/alembic/versions/20260129-172838_a251bdccb11f_add_gc_neighbor_and_is_dense_region_.py b/alembic/pfsa-db01-gb/alembic/versions/20260129-172838_a251bdccb11f_add_gc_neighbor_and_is_dense_region_.py
new file mode 100644
index 0000000..3b97b8f
--- /dev/null
+++ b/alembic/pfsa-db01-gb/alembic/versions/20260129-172838_a251bdccb11f_add_gc_neighbor_and_is_dense_region_.py
@@ -0,0 +1,40 @@
+"""add gc_neighbor and is_dense_region columns
+
+Revision ID: a251bdccb11f
+Revises: 385b6cdf44f7
+Create Date: 2026-01-29 17:28:38.712851
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = 'a251bdccb11f'
+down_revision = '385b6cdf44f7'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('fluxstd', sa.Column('is_gc_neighbor', sa.Boolean(), nullable=True, comment='Flag for globular cluster neighbor'))
+    op.add_column('fluxstd', sa.Column('is_dense_region', sa.Boolean(), nullable=True, comment='Flag for dense stellar region'))
+    op.alter_column('fluxstd', 'obj_id',
+               existing_type=sa.BIGINT(),
+               comment='source_id (e.g., Gaia EDR3, DR3, etc.)',
+               existing_comment='Gaia EDR3 sourceid',
+               existing_nullable=False)
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.alter_column('fluxstd', 'obj_id',
+               existing_type=sa.BIGINT(),
+               comment='Gaia EDR3 sourceid',
+               existing_comment='source_id (e.g., Gaia EDR3, DR3, etc.)',
+               existing_nullable=False)
+    op.drop_column('fluxstd', 'is_dense_region')
+    op.drop_column('fluxstd', 'is_gc_neighbor')
+    # ### end Alembic commands ###
diff --git a/diagrams/erdiagram_targetdb-20260129174351.pdf b/diagrams/erdiagram_targetdb-20260129174351.pdf
new file mode 100644
index 0000000..df57a96
Binary files /dev/null and b/diagrams/erdiagram_targetdb-20260129174351.pdf differ
diff --git a/src/targetdb/models/fluxstd.py b/src/targetdb/models/fluxstd.py
index 5fa6ca6..e3fe659 100644
--- a/src/targetdb/models/fluxstd.py
+++ b/src/targetdb/models/fluxstd.py
@@ -51,8 +51,8 @@ class fluxstd(Base):
     obj_id = Column(
         BigInteger,
         nullable=False,
-        comment="Gaia EDR3 sourceid",
-    )  # xxxx: need to understand more
+        comment="source_id (e.g., Gaia EDR3, DR3, etc.)",
+    )
 
     ra = Column(Float, nullable=False, comment="RA (ICRS, degree)")
     dec = Column(Float, nullable=False, comment="Dec (ICRS, degree)")
@@ -209,6 +209,16 @@ class fluxstd(Base):
         default=False,
         comment="Flag for F-star from Gaia (Teff=6000-7500K if True)",
     )
+    is_gc_neighbor = Column(
+        Boolean,
+        default=False,
+        comment="Flag for globular cluster neighbor",
+    )
+    is_dense_region = Column(
+        Boolean,
+        default=False,
+        comment="Flag for dense stellar region",
+    )
 
     # version string
     version = Column(
@@ -302,6 +312,8 @@ def __init__(
         teff_gspphot_lower,
         teff_gspphot_upper,
         is_fstar_gaia,
+        is_gc_neighbor,
+        is_dense_region,
         version,
         created_at,
         updated_at,
@@ -364,5 +376,7 @@ def __init__(
         self.teff_gspphot_lower = teff_gspphot_lower
         self.teff_gspphot_upper = teff_gspphot_upper
         self.is_fstar_gaia = is_fstar_gaia
+        self.is_gc_neighbor = is_gc_neighbor
+        self.is_dense_region = is_dense_region
         self.created_at = created_at
         self.updated_at = updated_at