diff --git a/contrib/ast-db-manage/config/versions/15b1430ad6f1_add_moh_passthrough_option_to_pjsip.py b/contrib/ast-db-manage/config/versions/15b1430ad6f1_add_moh_passthrough_option_to_pjsip.py
index 725238cab17bca65928039084c2bb44f830f5119..2456dac6e50a0c481628d830dc3245443a0dd009 100644
--- a/contrib/ast-db-manage/config/versions/15b1430ad6f1_add_moh_passthrough_option_to_pjsip.py
+++ b/contrib/ast-db-manage/config/versions/15b1430ad6f1_add_moh_passthrough_option_to_pjsip.py
@@ -27,5 +27,7 @@ def upgrade():
     op.add_column('ps_endpoints', sa.Column('moh_passthrough', yesno_values))
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_moh_passthrough_yesno_values','ps_endpoints')
     with op.batch_alter_table('ps_endpoints') as batch_op:
         batch_op.drop_column('moh_passthrough')
diff --git a/contrib/ast-db-manage/config/versions/15db7b91a97a_add_rtcp_mux.py b/contrib/ast-db-manage/config/versions/15db7b91a97a_add_rtcp_mux.py
index 8b0214a171446dc37ec3e13fc84ee6c5b03bfa96..de9e10ae3329978e0f9ba8214430d4f78abab3c0 100644
--- a/contrib/ast-db-manage/config/versions/15db7b91a97a_add_rtcp_mux.py
+++ b/contrib/ast-db-manage/config/versions/15db7b91a97a_add_rtcp_mux.py
@@ -28,4 +28,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_rtcp_mux_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'rtcp_mux')
diff --git a/contrib/ast-db-manage/config/versions/23530d604b96_add_rpid_immediate.py b/contrib/ast-db-manage/config/versions/23530d604b96_add_rpid_immediate.py
index dc0c01c24c3048b5ddbc775c5efb912e70a16fe8..b3ffaeedc57baa96d0f9667de36fc4f239785b32 100644
--- a/contrib/ast-db-manage/config/versions/23530d604b96_add_rpid_immediate.py
+++ b/contrib/ast-db-manage/config/versions/23530d604b96_add_rpid_immediate.py
@@ -45,4 +45,6 @@ def upgrade():
     op.add_column('ps_endpoints', sa.Column('rpid_immediate', yesno_values))
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_rpid_immediate_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'rpid_immediate')
diff --git a/contrib/ast-db-manage/config/versions/26d7f3bf0fa5_add_bind_rtp_to_media_address_to_pjsip.py b/contrib/ast-db-manage/config/versions/26d7f3bf0fa5_add_bind_rtp_to_media_address_to_pjsip.py
index e7c11da19259133cc38cd5b5eddca1d489078243..ce2ac1e5e1a0fe33a3ca576a1c1d77b327db1a05 100644
--- a/contrib/ast-db-manage/config/versions/26d7f3bf0fa5_add_bind_rtp_to_media_address_to_pjsip.py
+++ b/contrib/ast-db-manage/config/versions/26d7f3bf0fa5_add_bind_rtp_to_media_address_to_pjsip.py
@@ -28,4 +28,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_bind_rtp_to_media_address_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'bind_rtp_to_media_address')
diff --git a/contrib/ast-db-manage/config/versions/28ab27a7826d_add_srv_lookups_to_identify.py b/contrib/ast-db-manage/config/versions/28ab27a7826d_add_srv_lookups_to_identify.py
index 8831e20023e5f5d2aa476c6f67ff3c563c3cdff1..9325da3eb2868f9ab4bf56eabf0b40c1d8cebae0 100644
--- a/contrib/ast-db-manage/config/versions/28ab27a7826d_add_srv_lookups_to_identify.py
+++ b/contrib/ast-db-manage/config/versions/28ab27a7826d_add_srv_lookups_to_identify.py
@@ -28,4 +28,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoint_id_ips_srv_lookups_yesno_values','ps_endpoint_id_ips')
     op.drop_column('ps_endpoint_id_ips', 'srv_lookups')
diff --git a/contrib/ast-db-manage/config/versions/28b8e71e541f_add_g726_non_standard.py b/contrib/ast-db-manage/config/versions/28b8e71e541f_add_g726_non_standard.py
index ad36bd9b7cd3c3b87271caf34532a8ba03687832..08e2e3f36e6b149eb62fcc183d87144e5920cbaf 100644
--- a/contrib/ast-db-manage/config/versions/28b8e71e541f_add_g726_non_standard.py
+++ b/contrib/ast-db-manage/config/versions/28b8e71e541f_add_g726_non_standard.py
@@ -27,4 +27,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_g726_non_standard_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'g726_non_standard')
diff --git a/contrib/ast-db-manage/config/versions/2fc7930b41b3_add_pjsip_endpoint_options_for_12_1.py b/contrib/ast-db-manage/config/versions/2fc7930b41b3_add_pjsip_endpoint_options_for_12_1.py
index d39ddb41a59be7870974aa9ceac0988ffb08402e..3ca16feaf84efd9f8afb505b917f5be6295dcbb8 100644
--- a/contrib/ast-db-manage/config/versions/2fc7930b41b3_add_pjsip_endpoint_options_for_12_1.py
+++ b/contrib/ast-db-manage/config/versions/2fc7930b41b3_add_pjsip_endpoint_options_for_12_1.py
@@ -142,6 +142,8 @@ def upgrade():
 def downgrade():
     ########################## drop columns ##########################
 
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_aors_support_path_yesno_values', 'ps_aors')
     op.drop_column('ps_aors', 'support_path')
     op.drop_column('ps_aors', 'outbound_proxy')
     op.drop_column('ps_aors', 'maximum_expiration')
@@ -153,6 +155,8 @@ def downgrade():
         new_column_name='mwi_fromuser', existing_type=sa.String(40))
 
     op.drop_column('ps_endpoints', 'set_var')
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_redirect_method_pjsip_redirect_method_values', 'ps_endpoints')
     op.drop_column('ps_endpoints', 'redirect_method')
     op.drop_column('ps_endpoints', 'media_address')
 
diff --git a/contrib/ast-db-manage/config/versions/371a3bf4143e_add_user_eq_phone_option_to_pjsip.py b/contrib/ast-db-manage/config/versions/371a3bf4143e_add_user_eq_phone_option_to_pjsip.py
index 145d6bea6520d9ffefad571df103c57a3b041a4b..29558cee1ba6bcd37e94cb79c35724e3cd85fa43 100644
--- a/contrib/ast-db-manage/config/versions/371a3bf4143e_add_user_eq_phone_option_to_pjsip.py
+++ b/contrib/ast-db-manage/config/versions/371a3bf4143e_add_user_eq_phone_option_to_pjsip.py
@@ -27,4 +27,6 @@ def upgrade():
     op.add_column('ps_endpoints', sa.Column('user_eq_phone', yesno_values))
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_user_eq_phone_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'user_eq_phone')
diff --git a/contrib/ast-db-manage/config/versions/3772f8f828da_update_identify_by.py b/contrib/ast-db-manage/config/versions/3772f8f828da_update_identify_by.py
index 92695b09fc0e9e18b4be9bea22852f633f158ff5..3c80f4806a2e2748f56730270dd1d3a7cbc6f188 100644
--- a/contrib/ast-db-manage/config/versions/3772f8f828da_update_identify_by.py
+++ b/contrib/ast-db-manage/config/versions/3772f8f828da_update_identify_by.py
@@ -16,6 +16,8 @@ import sqlalchemy as sa
 
 def enum_update(table_name, column_name, enum_name, enum_values):
     if op.get_context().bind.dialect.name != 'postgresql':
+        if op.get_context().bind.dialect.name == 'mssql':
+            op.drop_constraint('ck_ps_endpoints_identify_by_pjsip_identify_by_values', 'ps_endpoints')
         op.alter_column(table_name, column_name,
                         type_=sa.Enum(*enum_values, name=enum_name))
         return
diff --git a/contrib/ast-db-manage/config/versions/3bcc0b5bc2c9_add_allow_reload_to_ps_transports.py b/contrib/ast-db-manage/config/versions/3bcc0b5bc2c9_add_allow_reload_to_ps_transports.py
index 0becc1e263b2abd833d0120079aeb4a6e0e2b346..093a5d4125039f3c84eb3f7af1c359cb196a738c 100644
--- a/contrib/ast-db-manage/config/versions/3bcc0b5bc2c9_add_allow_reload_to_ps_transports.py
+++ b/contrib/ast-db-manage/config/versions/3bcc0b5bc2c9_add_allow_reload_to_ps_transports.py
@@ -22,4 +22,6 @@ def upgrade():
     op.add_column('ps_transports', sa.Column('allow_reload', yesno_values))
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_transports_allow_reload_yesno_values','ps_transports')
     op.drop_column('ps_transports', 'allow_reload')
diff --git a/contrib/ast-db-manage/config/versions/4468b4a91372_add_pjsip_asymmetric_rtp_codec.py b/contrib/ast-db-manage/config/versions/4468b4a91372_add_pjsip_asymmetric_rtp_codec.py
index c121495e2d2d57664ffd464e0a63ceeed5940919..1a8ede6cd1497168c6a7888d7c03bee2eb6b4bd5 100644
--- a/contrib/ast-db-manage/config/versions/4468b4a91372_add_pjsip_asymmetric_rtp_codec.py
+++ b/contrib/ast-db-manage/config/versions/4468b4a91372_add_pjsip_asymmetric_rtp_codec.py
@@ -28,4 +28,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_asymmetric_rtp_codec_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'asymmetric_rtp_codec')
diff --git a/contrib/ast-db-manage/config/versions/4c573e7135bd_fix_tos_field_types.py b/contrib/ast-db-manage/config/versions/4c573e7135bd_fix_tos_field_types.py
index 17906ae19da8a4d2c10a3f67d9d0e7c036312934..08211647ce02475946c3533b51c4bfa7548a19bd 100644
--- a/contrib/ast-db-manage/config/versions/4c573e7135bd_fix_tos_field_types.py
+++ b/contrib/ast-db-manage/config/versions/4c573e7135bd_fix_tos_field_types.py
@@ -28,7 +28,7 @@ def upgrade():
     op.alter_column('ps_transports', 'tos', type_=sa.String(10))
 
     # Can't cast YENO_VALUES to Integers, so dropping and adding is required
-    op.drop_column('ps_transports', 'cos')
+    op.drop_column('ps_transports', 'cos', schema=None, mssql_drop_check=True)
     op.add_column('ps_transports', sa.Column('cos', sa.Integer))
 
 def downgrade():
@@ -45,6 +45,8 @@ def downgrade():
     op.add_column('ps_endpoints', sa.Column('cos_audio', yesno_values))
     op.add_column('ps_endpoints', sa.Column('cos_video', yesno_values))
 
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_transports_tos_yesno_values', 'ps_transports')
     op.drop_column('ps_transports', 'tos')
     op.add_column('ps_transports', sa.Column('tos', yesno_values))
     # Can't cast integers to YESNO_VALUES, so dropping and adding is required
diff --git a/contrib/ast-db-manage/config/versions/5139253c0423_make_q_member_uniqueid_autoinc.py b/contrib/ast-db-manage/config/versions/5139253c0423_make_q_member_uniqueid_autoinc.py
index 72f5ee169615b051312d5427017ace299571f243..7efd8b296149b0039681e814575265df6501198c 100644
--- a/contrib/ast-db-manage/config/versions/5139253c0423_make_q_member_uniqueid_autoinc.py
+++ b/contrib/ast-db-manage/config/versions/5139253c0423_make_q_member_uniqueid_autoinc.py
@@ -38,7 +38,7 @@ def upgrade():
     op.drop_column('queue_members', 'uniqueid')
     op.add_column('queue_members', sa.Column(name='uniqueid', type_=sa.Integer,
                                              nullable=False, unique=True))
-    # The postgres backend does not like the autoincrement needed for
+    # The postgres and mssql backends do not like the autoincrement needed for
     # mysql here.  It is just the backend that is giving a warning and
     # not the database itself.
     op.alter_column(table_name='queue_members', column_name='uniqueid',
@@ -49,5 +49,7 @@ def upgrade():
 def downgrade():
     # Was unable to find a way to use op.alter_column() to remove the
     # unique index property.
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('uq_queue_members_uniqueid', 'queue_members')
     op.drop_column('queue_members', 'uniqueid')
     op.add_column('queue_members', sa.Column(name='uniqueid', type_=sa.String(80), nullable=False))
diff --git a/contrib/ast-db-manage/config/versions/51f8cb66540e_add_further_dtls_options.py b/contrib/ast-db-manage/config/versions/51f8cb66540e_add_further_dtls_options.py
index c2dacda2c682ce7e4f4bbeae42e08e481a23e96a..2eea7139a2c17639e90b68b104eb31527dffb1ce 100644
--- a/contrib/ast-db-manage/config/versions/51f8cb66540e_add_further_dtls_options.py
+++ b/contrib/ast-db-manage/config/versions/51f8cb66540e_add_further_dtls_options.py
@@ -28,5 +28,8 @@ def upgrade():
     op.add_column('ps_endpoints', sa.Column('media_use_received_transport', yesno_values))
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_force_avp_yesno_values', 'ps_endpoints')
+        op.drop_constraint('ck_ps_endpoints_media_use_received_transport_yesno_values', 'ps_endpoints')
     op.drop_column('ps_endpoints', 'force_avp')
     op.drop_column('ps_endpoints', 'media_use_received_transport')
diff --git a/contrib/ast-db-manage/config/versions/5950038a6ead_fix_pjsip_verifiy_typo.py b/contrib/ast-db-manage/config/versions/5950038a6ead_fix_pjsip_verifiy_typo.py
index 28ebc8b1773f606aa2fb5492aac52ace211c9523..a1154a30ee26df4513dbdfdc57810c645e6c63c2 100644
--- a/contrib/ast-db-manage/config/versions/5950038a6ead_fix_pjsip_verifiy_typo.py
+++ b/contrib/ast-db-manage/config/versions/5950038a6ead_fix_pjsip_verifiy_typo.py
@@ -11,19 +11,32 @@ revision = '5950038a6ead'
 down_revision = 'd39508cb8d8'
 
 from alembic import op
+import sqlalchemy as sa
 from sqlalchemy.dialects.postgresql import ENUM
 
 YESNO_NAME = 'yesno_values'
 YESNO_VALUES = ['yes', 'no']
 
-
 def upgrade():
     yesno_values = ENUM(*YESNO_VALUES, name=YESNO_NAME, create_type=False)
-    op.alter_column('ps_transports', 'verifiy_server', type_=yesno_values,
-                    new_column_name='verify_server')
+
+    if op.get_context().bind.dialect.name != 'mssql':
+        op.alter_column('ps_transports', 'verifiy_server', type_=yesno_values,
+                        new_column_name='verify_server')
+    else:
+        op.alter_column('ps_transports', 'verifiy_server', existing_type=yesno_values, type_=sa.String(3),
+                        new_column_name='verify_server')
+        yesno_values = ENUM(*YESNO_VALUES, name=YESNO_NAME, create_type=True)
+        op.alter_column('ps_transports', 'verify_server', existing_type=sa.String(3), type_=yesno_values)
 
 
 def downgrade():
     yesno_values = ENUM(*YESNO_VALUES, name=YESNO_NAME, create_type=False)
-    op.alter_column('ps_transports', 'verify_server', type_=yesno_values,
-                    new_column_name='verifiy_server')
+    if op.get_context().bind.dialect.name != 'mssql':
+        op.alter_column('ps_transports', 'verify_server', type_=yesno_values,
+                        new_column_name='verifiy_server')
+    else:
+        op.alter_column('ps_transports', 'verify_server', existing_type=yesno_values, type_=sa.String(3),
+                        new_column_name='verifiy_server')
+        yesno_values = ENUM(*YESNO_VALUES, name=YESNO_NAME, create_type=True)
+        op.alter_column('ps_transports', 'verifiy_server', existing_type=sa.String(3), type_=yesno_values)
diff --git a/contrib/ast-db-manage/config/versions/837aa67461fb_ps_contacts_add_authenticate_qualify.py b/contrib/ast-db-manage/config/versions/837aa67461fb_ps_contacts_add_authenticate_qualify.py
index 76faf394cfdda506f55ef9fae80774d111c24518..033a999af6bd763ff0a2d12aa7f9d62ec20e8066 100644
--- a/contrib/ast-db-manage/config/versions/837aa67461fb_ps_contacts_add_authenticate_qualify.py
+++ b/contrib/ast-db-manage/config/versions/837aa67461fb_ps_contacts_add_authenticate_qualify.py
@@ -28,5 +28,7 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_contacts_authenticate_qualify_yesno_values','ps_contacts')
     op.drop_column('ps_contacts', 'authenticate_qualify')
 
diff --git a/contrib/ast-db-manage/config/versions/86bb1efa278d_add_ps_endpoints_refer_blind_progress.py b/contrib/ast-db-manage/config/versions/86bb1efa278d_add_ps_endpoints_refer_blind_progress.py
index 9b0f6d4d08a32662da42eb82b72fd68d2d1df2fb..a46ed0c5d6abafa932ca3377f5c86f79510bc441 100644
--- a/contrib/ast-db-manage/config/versions/86bb1efa278d_add_ps_endpoints_refer_blind_progress.py
+++ b/contrib/ast-db-manage/config/versions/86bb1efa278d_add_ps_endpoints_refer_blind_progress.py
@@ -27,4 +27,6 @@ def upgrade():
     op.add_column('ps_endpoints', sa.Column('refer_blind_progress', yesno_values))
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_refer_blind_progress_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'refer_blind_progress')
diff --git a/contrib/ast-db-manage/config/versions/8d478ab86e29_pjsip_add_disable_multi_domain.py b/contrib/ast-db-manage/config/versions/8d478ab86e29_pjsip_add_disable_multi_domain.py
index a782685847d1d0cec005432a4174ad386d8e000b..a8d7b48ca6906ef6c09877236d224ec7b2cee145 100644
--- a/contrib/ast-db-manage/config/versions/8d478ab86e29_pjsip_add_disable_multi_domain.py
+++ b/contrib/ast-db-manage/config/versions/8d478ab86e29_pjsip_add_disable_multi_domain.py
@@ -28,4 +28,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_globals_disable_multi_domain_yesno_values','ps_globals')
     op.drop_column('ps_globals', 'disable_multi_domain')
diff --git a/contrib/ast-db-manage/config/versions/8fce4c573e15_add_pjsip_allow_overlap.py b/contrib/ast-db-manage/config/versions/8fce4c573e15_add_pjsip_allow_overlap.py
index 24057ecc878e451490f0bb4a89a59d1bb46a32b1..539944e29c1f87eb32257c53d6a87a146420507d 100644
--- a/contrib/ast-db-manage/config/versions/8fce4c573e15_add_pjsip_allow_overlap.py
+++ b/contrib/ast-db-manage/config/versions/8fce4c573e15_add_pjsip_allow_overlap.py
@@ -28,4 +28,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_allow_overlap_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'allow_overlap')
diff --git a/contrib/ast-db-manage/config/versions/945b1098bdd_add_media_encryption_optimistic_to_pjsip.py b/contrib/ast-db-manage/config/versions/945b1098bdd_add_media_encryption_optimistic_to_pjsip.py
index 7a463f0575313d93fa7b2751df8dc0b6e1fb925a..61ec27266745bc9397c35ac6f98dca018ae0ef8e 100644
--- a/contrib/ast-db-manage/config/versions/945b1098bdd_add_media_encryption_optimistic_to_pjsip.py
+++ b/contrib/ast-db-manage/config/versions/945b1098bdd_add_media_encryption_optimistic_to_pjsip.py
@@ -28,4 +28,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_media_encryption_optimistic_yesno_values','ps_endpoints')
     op.drop_column('ps_endpoints', 'media_encryption_optimistic')
diff --git a/contrib/ast-db-manage/config/versions/a6ef36f1309_ps_globals_add_ignore_uri_user_options.py b/contrib/ast-db-manage/config/versions/a6ef36f1309_ps_globals_add_ignore_uri_user_options.py
index 1556521d55279674429bd50d47f0fdbc42c64ff2..55d3d3811a9411c30d596a82fef9546cf0b46c46 100644
--- a/contrib/ast-db-manage/config/versions/a6ef36f1309_ps_globals_add_ignore_uri_user_options.py
+++ b/contrib/ast-db-manage/config/versions/a6ef36f1309_ps_globals_add_ignore_uri_user_options.py
@@ -28,5 +28,7 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_globals_ignore_uri_user_options_yesno_values','ps_globals')
     op.drop_column('ps_globals', 'ignore_uri_user_options')
 
diff --git a/contrib/ast-db-manage/config/versions/b83645976fdd_add_dtls_fingerprint_to_ps_endpoints.py b/contrib/ast-db-manage/config/versions/b83645976fdd_add_dtls_fingerprint_to_ps_endpoints.py
index 3d4f74de51b3862b0fafa496fedac5c32140f486..42b522c1bb7cc336392cea117e0ba7a0c8c52ed3 100644
--- a/contrib/ast-db-manage/config/versions/b83645976fdd_add_dtls_fingerprint_to_ps_endpoints.py
+++ b/contrib/ast-db-manage/config/versions/b83645976fdd_add_dtls_fingerprint_to_ps_endpoints.py
@@ -31,6 +31,8 @@ def upgrade():
 def downgrade():
     context = op.get_context()
 
+    if context.bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_dtls_fingerprint_sha_hash_values', 'ps_endpoints')
     op.drop_column('ps_endpoints', 'dtls_fingerprint')
 
     if context.bind.dialect.name == 'postgresql':
diff --git a/contrib/ast-db-manage/config/versions/c7a44a5a0851_pjsip_add_global_mwi_options.py b/contrib/ast-db-manage/config/versions/c7a44a5a0851_pjsip_add_global_mwi_options.py
index d3efa2278a59d503a34ef5136c218f52d51993af..c762fc430ab427473a6540cca68b224773fae3d6 100644
--- a/contrib/ast-db-manage/config/versions/c7a44a5a0851_pjsip_add_global_mwi_options.py
+++ b/contrib/ast-db-manage/config/versions/c7a44a5a0851_pjsip_add_global_mwi_options.py
@@ -32,4 +32,6 @@ def upgrade():
 def downgrade():
     op.drop_column('ps_globals', 'mwi_tps_queue_high')
     op.drop_column('ps_globals', 'mwi_tps_queue_low')
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_globals_mwi_disable_initial_unsolicited_yesno_values','ps_globals')
     op.drop_column('ps_globals', 'mwi_disable_initial_unsolicited')
diff --git a/contrib/ast-db-manage/config/versions/d7983954dd96_add_ps_endpoints_notify_early_inuse_.py b/contrib/ast-db-manage/config/versions/d7983954dd96_add_ps_endpoints_notify_early_inuse_.py
index e1dcdd133b16bd39b0e84e83be172c3d0f9aa40a..a5419a15ffddf54ae4dff171c8300b94090cc11f 100644
--- a/contrib/ast-db-manage/config/versions/d7983954dd96_add_ps_endpoints_notify_early_inuse_.py
+++ b/contrib/ast-db-manage/config/versions/d7983954dd96_add_ps_endpoints_notify_early_inuse_.py
@@ -27,4 +27,6 @@ def upgrade():
     op.add_column('ps_endpoints', sa.Column('notify_early_inuse_ringing', yesno_values))
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_endpoints_notify_early_inuse_ringing_yesno_values', 'ps_endpoints')
     op.drop_column('ps_endpoints', 'notify_early_inuse_ringing')
diff --git a/contrib/ast-db-manage/config/versions/dbc44d5a908_add_missing_columns_to_sys_and_reg.py b/contrib/ast-db-manage/config/versions/dbc44d5a908_add_missing_columns_to_sys_and_reg.py
index 8aa16f1552eb3f121d4e1783368933f2700982a6..9acd4a091e8cb2c143f98531a405134996d4ca8b 100644
--- a/contrib/ast-db-manage/config/versions/dbc44d5a908_add_missing_columns_to_sys_and_reg.py
+++ b/contrib/ast-db-manage/config/versions/dbc44d5a908_add_missing_columns_to_sys_and_reg.py
@@ -29,6 +29,9 @@ def upgrade():
     op.add_column('ps_registrations', sa.Column('endpoint', sa.String(40)))
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_systems_disable_tcp_switch_yesno_values','ps_systems')
+        op.drop_constraint('ck_ps_registrations_line_yesno_values','ps_registrations')
     op.drop_column('ps_systems', 'disable_tcp_switch')
     op.drop_column('ps_registrations', 'line')
     op.drop_column('ps_registrations', 'endpoint')
diff --git a/contrib/ast-db-manage/config/versions/e96a0b8071c_increase_pjsip_column_size.py b/contrib/ast-db-manage/config/versions/e96a0b8071c_increase_pjsip_column_size.py
index 9c00c012ef7b3636cb66790b51893ade219740cb..da103b1f0b0148d7bbed2efb33daebf476baf76a 100644
--- a/contrib/ast-db-manage/config/versions/e96a0b8071c_increase_pjsip_column_size.py
+++ b/contrib/ast-db-manage/config/versions/e96a0b8071c_increase_pjsip_column_size.py
@@ -28,7 +28,13 @@ def upgrade():
 def downgrade():
     op.alter_column('ps_globals', 'user_agent', type_=sa.String(40))
 
-    op.alter_column('ps_contacts', 'id', type_=sa.String(40))
+    if op.get_context().bind.dialect.name != 'mssql':
+        op.alter_column('ps_contacts', 'id', type_=sa.String(40))
+    else:
+        op.drop_constraint('uq_ps_contacts_id', 'ps_contacts')
+        op.drop_index('ps_contacts_id', 'ps_contacts')
+        op.alter_column('ps_contacts', 'id', type_=sa.String(40))
+        op.create_index('ps_contacts_id', 'ps_contacts', ['id'])
     op.alter_column('ps_contacts', 'uri', type_=sa.String(40))
     op.alter_column('ps_contacts', 'user_agent', type_=sa.String(40))
 
diff --git a/contrib/ast-db-manage/config/versions/ef7efc2d3964_ps_contacts_add_endpoint_and_modify_.py b/contrib/ast-db-manage/config/versions/ef7efc2d3964_ps_contacts_add_endpoint_and_modify_.py
index 43d4028f2b08f8bdcf9ba336f42fc40c2e17dfc7..0ac63c83a280582057deb4bb86e5c116ca109305 100644
--- a/contrib/ast-db-manage/config/versions/ef7efc2d3964_ps_contacts_add_endpoint_and_modify_.py
+++ b/contrib/ast-db-manage/config/versions/ef7efc2d3964_ps_contacts_add_endpoint_and_modify_.py
@@ -27,7 +27,11 @@ def upgrade():
     op.create_index('ps_contacts_qualifyfreq_exp', 'ps_contacts', ['qualify_frequency', 'expiration_time'])
     op.create_index('ps_aors_qualifyfreq_contact', 'ps_aors', ['qualify_frequency', 'contact'])
 def downgrade():
-    op.drop_index('ps_aors_qualifyfreq_contact')
-    op.drop_index('ps_contacts_qualifyfreq_exp')
+    if op.get_context().bind.dialect.name != 'mssql':
+        op.drop_index('ps_aors_qualifyfreq_contact')
+        op.drop_index('ps_contacts_qualifyfreq_exp')
+    else:
+        op.drop_index('ps_aors_qualifyfreq_contact', table_name='ps_aors')
+        op.drop_index('ps_contacts_qualifyfreq_exp', table_name='ps_contacts')
     op.drop_column('ps_contacts', 'endpoint')
     op.alter_column('ps_contacts', 'expiration_time', type_=sa.String(40))
diff --git a/contrib/ast-db-manage/config/versions/f3d1c5d38b56_add_prune_on_boot.py b/contrib/ast-db-manage/config/versions/f3d1c5d38b56_add_prune_on_boot.py
index bea167369a36a0e0aa25ab7a5cd4986ad0a49391..179efba1315c10d5237e2dc09a9a475d25bde724 100644
--- a/contrib/ast-db-manage/config/versions/f3d1c5d38b56_add_prune_on_boot.py
+++ b/contrib/ast-db-manage/config/versions/f3d1c5d38b56_add_prune_on_boot.py
@@ -28,4 +28,6 @@ def upgrade():
 
 
 def downgrade():
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_contacts_prune_on_boot_yesno_values', 'ps_contacts')
     op.drop_column('ps_contacts', 'prune_on_boot')
diff --git a/contrib/ast-db-manage/config/versions/f638dbe2eb23_symmetric_transport.py b/contrib/ast-db-manage/config/versions/f638dbe2eb23_symmetric_transport.py
index 51b5066f5706c8b2615919328609d5cb110b6bfc..0585aa52d3d87c7506d0deccee589738094d33be 100644
--- a/contrib/ast-db-manage/config/versions/f638dbe2eb23_symmetric_transport.py
+++ b/contrib/ast-db-manage/config/versions/f638dbe2eb23_symmetric_transport.py
@@ -29,4 +29,6 @@ def upgrade():
 
 def downgrade():
     op.drop_column('ps_subscription_persistence', 'contact_uri')
+    if op.get_context().bind.dialect.name == 'mssql':
+        op.drop_constraint('ck_ps_transports_symmetric_transport_yesno_values','ps_transports')
     op.drop_column('ps_transports', 'symmetric_transport')
diff --git a/contrib/ast-db-manage/env.py b/contrib/ast-db-manage/env.py
index a903451b4c64239c96452814706f4b3fa6752f9f..1864239135f1ece54fd9e866259e1f6a2da34c52 100644
--- a/contrib/ast-db-manage/env.py
+++ b/contrib/ast-db-manage/env.py
@@ -2,7 +2,8 @@ from __future__ import with_statement
 from alembic import context
 from alembic.script import ScriptDirectory
 from alembic.operations import Operations
-from sqlalchemy import engine_from_config, pool
+from sqlalchemy import engine_from_config, pool, MetaData
+from sqlalchemy.ext.declarative import declarative_base
 from logging.config import fileConfig
 import logging
 
@@ -17,12 +18,24 @@ try:
 except:
     pass
 
+## below block is needed for mssql
+meta = MetaData(naming_convention = {
+	"ix": 'ix_%(column_0_label)s',
+	"uq": "uq_%(table_name)s_%(column_0_name)s",
+	"ck": "ck_%(table_name)s_%(column_0_name)s_%(constraint_name)s",
+	"fk": "fk_%(table_name)s_%(column_0_name)s_%(referred_table_name)s",
+	"pk": "pk_%(table_name)s"
+})
+Base = declarative_base(metadata=meta)
+
 logger = logging.getLogger('alembic.runtime.setup')
 # add your model's MetaData object here
 # for 'autogenerate' support
 # from myapp import mymodel
 # target_metadata = mymodel.Base.metadata
 target_metadata = None
+#Comment above line and uncomment below line for mssql
+#target_metadata = Base.metadata
 
 # other values from the config, defined by the needs of env.py,
 # can be acquired:
@@ -42,7 +55,7 @@ def run_migrations_offline():
 
     """
     url = config.get_main_option("sqlalchemy.url")
-    context.configure(url=url)
+    context.configure(url=url,target_metadata=target_metadata)
 
     with context.begin_transaction():
         context.run_migrations()