diff --git a/alembic/versions/cac6140fdbf9_initial_migration.py b/alembic/versions/f1540475192e_initial_migration.py
similarity index 97%
rename from alembic/versions/cac6140fdbf9_initial_migration.py
rename to alembic/versions/f1540475192e_initial_migration.py
index a5017b72..fe6c114d 100644
--- a/alembic/versions/cac6140fdbf9_initial_migration.py
+++ b/alembic/versions/f1540475192e_initial_migration.py
@@ -1,19 +1,18 @@
 """Initial migration
 
-Revision ID: cac6140fdbf9
-Revises: 
-Create Date: 2024-05-13 16:18:47.291448
+Revision ID: f1540475192e
+Revises:
+Create Date: 2024-05-13 17:48:42.947299
 
 """
 from typing import Sequence, Union
 
-from alembic import op
 import sqlalchemy as sa
-from sqlalchemy.dialects import mysql
-from sqlalchemy.dialects import oracle
+from alembic import op
+from sqlalchemy.dialects import mysql, oracle
 
 # revision identifiers, used by Alembic.
-revision: str = 'cac6140fdbf9'
+revision: str = 'f1540475192e'
 down_revision: Union[str, None] = None
 branch_labels: Union[str, Sequence[str], None] = None
 depends_on: Union[str, Sequence[str], None] = None
@@ -21,7 +20,7 @@
 
 def upgrade() -> None:
     # ### commands auto generated by Alembic - please adjust! ###
-    op.execute("CREATE SCHEMA IF NOT EXISTS cdb_latiss")
+    op.execute('CREATE SCHEMA IF NOT EXISTS cdb_latiss')
     op.create_table('exposure',
     sa.Column('exposure_id', sa.BIGINT().with_variant(mysql.BIGINT(), 'mysql').with_variant(oracle.NUMBER(precision=38, scale=0, asdecimal=False), 'oracle').with_variant(sa.BIGINT(), 'postgresql'), nullable=False, comment='Unique identifier.'),
     sa.Column('exposure_name', sa.VARCHAR(length=20).with_variant(mysql.VARCHAR(length=20), 'mysql').with_variant(oracle.VARCHAR2(length=20), 'oracle').with_variant(sa.VARCHAR(length=20), 'postgresql'), nullable=False, comment='Official name of the exposure.'),
@@ -80,15 +79,15 @@ def upgrade() -> None:
     schema='cdb_latiss'
     )
     op.create_table('exposure_flexdata_schema',
-    sa.Column('key', sa.TEXT().with_variant(mysql.LONGTEXT(), 'mysql').with_variant(sa.CLOB(), 'oracle').with_variant(sa.TEXT(), 'postgresql'), nullable=True, comment='Name of key.'),
+    sa.Column('key', sa.TEXT().with_variant(mysql.LONGTEXT(), 'mysql').with_variant(sa.CLOB(), 'oracle').with_variant(sa.TEXT(), 'postgresql'), nullable=False, comment='Name of key.'),
     sa.Column('dtype', sa.TEXT().with_variant(mysql.LONGTEXT(), 'mysql').with_variant(sa.CLOB(), 'oracle').with_variant(sa.TEXT(), 'postgresql'), nullable=True, comment='Name of the data type of the value, one of bool, int, float, str.'),
     sa.Column('doc', sa.TEXT().with_variant(mysql.LONGTEXT(), 'mysql').with_variant(sa.CLOB(), 'oracle').with_variant(sa.TEXT(), 'postgresql'), nullable=True, comment='Documentation string.  Can include units and IVOA UCD.'),
     sa.PrimaryKeyConstraint('key'),
     schema='cdb_latiss'
     )
     op.create_table('exposure_flexdata',
-    sa.Column('obs_id', sa.BIGINT().with_variant(mysql.BIGINT(), 'mysql').with_variant(oracle.NUMBER(precision=38, scale=0, asdecimal=False), 'oracle').with_variant(sa.BIGINT(), 'postgresql'), nullable=True, comment='Unique identifier.'),
-    sa.Column('key', sa.TEXT().with_variant(mysql.LONGTEXT(), 'mysql').with_variant(sa.CLOB(), 'oracle').with_variant(sa.TEXT(), 'postgresql'), nullable=True, comment='Name of key.'),
+    sa.Column('obs_id', sa.BIGINT().with_variant(mysql.BIGINT(), 'mysql').with_variant(oracle.NUMBER(precision=38, scale=0, asdecimal=False), 'oracle').with_variant(sa.BIGINT(), 'postgresql'), nullable=False, comment='Unique identifier.'),
+    sa.Column('key', sa.TEXT().with_variant(mysql.LONGTEXT(), 'mysql').with_variant(sa.CLOB(), 'oracle').with_variant(sa.TEXT(), 'postgresql'), nullable=False, comment='Name of key.'),
     sa.Column('value', sa.TEXT().with_variant(mysql.LONGTEXT(), 'mysql').with_variant(sa.CLOB(), 'oracle').with_variant(sa.TEXT(), 'postgresql'), nullable=True, comment='Content of value as a string.'),
     sa.ForeignKeyConstraint(['key'], ['cdb_latiss.exposure_flexdata_schema.key'], name='fk_key'),
     sa.ForeignKeyConstraint(['obs_id'], ['cdb_latiss.exposure.exposure_id'], name='fk_obs_id'),