diff --git a/packages/nc-gui/components/project/spreadsheet/components/headerCell.vue b/packages/nc-gui/components/project/spreadsheet/components/headerCell.vue
index 775f2d1d43..747e37fc32 100644
--- a/packages/nc-gui/components/project/spreadsheet/components/headerCell.vue
+++ b/packages/nc-gui/components/project/spreadsheet/components/headerCell.vue
@@ -115,7 +115,7 @@
         <v-divider />
         <v-card-text class="mt-4 title">
           Do you want to delete <span class="font-weight-bold">'{{
-            column.cn
+            column._cn
           }}'</span> column ?
         </v-card-text>
         <v-divider />
diff --git a/packages/nc-gui/components/project/spreadsheet/components/virtualHeaderCell.vue b/packages/nc-gui/components/project/spreadsheet/components/virtualHeaderCell.vue
index 5670149810..af898d7196 100644
--- a/packages/nc-gui/components/project/spreadsheet/components/virtualHeaderCell.vue
+++ b/packages/nc-gui/components/project/spreadsheet/components/virtualHeaderCell.vue
@@ -82,7 +82,7 @@
         <v-divider />
         <v-card-text class="mt-4 title">
           Do you want to delete <span class="font-weight-bold">'{{
-            column.cn
+            column._cn
           }}'</span> column ?
         </v-card-text>
         <v-divider />
diff --git a/packages/nc-gui/components/project/tableTabs/logicGrpc.vue b/packages/nc-gui/components/project/tableTabs/logicGrpc.vue
index ff400b865d..8f78dcbcf2 100644
--- a/packages/nc-gui/components/project/tableTabs/logicGrpc.vue
+++ b/packages/nc-gui/components/project/tableTabs/logicGrpc.vue
@@ -256,11 +256,11 @@ export default {
       }])
       this.messages = tableMeta.messages
       this.services = tableMeta.services
-      if (tableMeta.schema_previous) {
-        this.schemaHistory = JSON.parse(tableMeta.schema_previous).reverse()
-      } else {
-        this.schemaHistory = []
-      }
+      // if (tableMeta.schema_previous) {
+      //   this.schemaHistory = JSON.parse(tableMeta.schema_previous).reverse()
+      // } else {
+      //   this.schemaHistory = []
+      // }
     },
     async loadRpcs() {
       this.rpcServices = (await this.$store.dispatch('sqlMgr/ActSqlOp', [{
diff --git a/packages/nc-gui/components/project/tableTabs/logicRest.vue b/packages/nc-gui/components/project/tableTabs/logicRest.vue
index 5f219d200d..3f12ea7ced 100644
--- a/packages/nc-gui/components/project/tableTabs/logicRest.vue
+++ b/packages/nc-gui/components/project/tableTabs/logicRest.vue
@@ -322,11 +322,11 @@ export default {
         tn: this.nodes.tn || this.nodes.view_name
       }])
       this.swaggerDoc = JSON.stringify(JSON.parse(tableMeta.schema), 0, 2)
-      if (tableMeta.schema_previous) {
-        this.swaggerDocHistory = JSON.parse(tableMeta.schema_previous).reverse().map(o => JSON.stringify(o, null, 2))
-      } else {
-        this.swaggerDocHistory = []
-      }
+      // if (tableMeta.schema_previous) {
+      //   this.swaggerDocHistory = JSON.parse(tableMeta.schema_previous).reverse().map(o => JSON.stringify(o, null, 2))
+      // } else {
+      //   this.swaggerDocHistory = []
+      // }
     },
     async saveSwaggerDoc() {
       this.edited = false
diff --git a/packages/nocodb/src/lib/noco/common/BaseApiBuilder.ts b/packages/nocodb/src/lib/noco/common/BaseApiBuilder.ts
index ac7f82a9a9..9df47da72e 100644
--- a/packages/nocodb/src/lib/noco/common/BaseApiBuilder.ts
+++ b/packages/nocodb/src/lib/noco/common/BaseApiBuilder.ts
@@ -1389,7 +1389,7 @@ export default abstract class BaseApiBuilder<T extends Noco> implements XcDynami
           continue;
         }
 
-        const tableMetaA = this.metas[meta.belongsTo[0].rtn];
+        const tableMetaA = this.  metas[meta.belongsTo[0].rtn];
         const tableMetaB = this.metas[meta.belongsTo[1].rtn];
 
         /*        // remove hasmany relation with associate table from tables
diff --git a/packages/nocodb/src/lib/noco/gql/GqlApiBuilder.ts b/packages/nocodb/src/lib/noco/gql/GqlApiBuilder.ts
index 05d5f7def6..9635e98761 100644
--- a/packages/nocodb/src/lib/noco/gql/GqlApiBuilder.ts
+++ b/packages/nocodb/src/lib/noco/gql/GqlApiBuilder.ts
@@ -112,7 +112,9 @@ export class GqlApiBuilder extends BaseApiBuilder<Noco> implements XcMetaMgr {
       }
     });
 
-    for (const {meta, id, title, schema_previous} of metas) {
+    for (const {meta, id, title,
+      // schema_previous
+    } of metas) {
       const metaObj = JSON.parse(meta);
       /* filter relation where this table is present */
       const hasMany = metaObj.hasMany.filter(({enabled}) => enabled)
@@ -127,15 +129,15 @@ export class GqlApiBuilder extends BaseApiBuilder<Noco> implements XcMetaMgr {
       const newSchema = this.schemas[title] = GqlXcSchemaFactory.create(this.connectionConfig, this.generateRendererArgs(ctx)).getString();
       if (oldSchema !== this.schemas[title]) {
         // keep upto 5 schema backup on table update
-        let previousSchemas = [oldSchema]
-        if (schema_previous) {
-          previousSchemas = [...JSON.parse(schema_previous), oldSchema].slice(-5);
-        }
+        // const previousSchemas = [oldSchema]
+        // if (schema_previous) {
+        //   previousSchemas = [...JSON.parse(schema_previous), oldSchema].slice(-5);
+        // }
         this.log(`onToggleModelRelation : Updating and taking backup of schema for '%s' table`, title)
 
         await this.xcMeta.metaUpdate(this.projectId, this.dbAlias, 'nc_models', {
           schema: newSchema,
-          schema_previous: JSON.stringify(previousSchemas)
+          // schema_previous: JSON.stringify(previousSchemas)
         }, {
           id
         });
@@ -1523,19 +1525,19 @@ export class GqlApiBuilder extends BaseApiBuilder<Noco> implements XcMetaMgr {
       if (oldSchema !== this.schemas[tn]) {
         this.log(`onTableUpdate :  Updating and taking backup of schema - '%s' table`, changeObj.tn);
 
-        const oldModel = await this.xcMeta.metaGet(this.projectId, this.dbAlias, 'nc_models', {
-          title: tn
-        });
+        // const oldModel = await this.xcMeta.metaGet(this.projectId, this.dbAlias, 'nc_models', {
+        //   title: tn
+        // });
 
         // keep upto 5 schema backup on table update
-        let previousSchemas = [oldSchema]
-        if (oldModel.schema_previous) {
-          previousSchemas = [...JSON.parse(oldModel.schema_previous), oldSchema].slice(-5);
-        }
+        // let previousSchemas = [oldSchema]
+        // if (oldModel.schema_previous) {
+        //   previousSchemas = [...JSON.parse(oldModel.schema_previous), oldSchema].slice(-5);
+        // }
 
         await this.xcMeta.metaUpdate(this.projectId, this.dbAlias, 'nc_models', {
           schema: this.schemas[tn],
-          schema_previous: JSON.stringify(previousSchemas)
+          // schema_previous: JSON.stringify(previousSchemas)
         }, {
           title: tn
         });
@@ -1567,19 +1569,19 @@ export class GqlApiBuilder extends BaseApiBuilder<Noco> implements XcMetaMgr {
 
         this.log(`onViewUpdate :  Updating and taking backup of schema - '%s' view`, viewName);
 
-        const oldModel = await this.xcMeta.metaGet(this.projectId, this.dbAlias, 'nc_models', {
-          title: viewName
-        });
+        // const oldModel = await this.xcMeta.metaGet(this.projectId, this.dbAlias, 'nc_models', {
+        //   title: viewName
+        // });
 
-        // keep upto 5 schema backup on table update
-        let previousSchemas = [oldSchema]
-        if (oldModel.schema_previous) {
-          previousSchemas = [...JSON.parse(oldModel.schema_previous), oldSchema].slice(-5);
-        }
+        // // keep upto 5 schema backup on table update
+        // let previousSchemas = [oldSchema]
+        // if (oldModel.schema_previous) {
+        //   previousSchemas = [...JSON.parse(oldModel.schema_previous), oldSchema].slice(-5);
+        // }
 
         await this.xcMeta.metaUpdate(this.projectId, this.dbAlias, 'nc_models', {
           schema: meta.schema,
-          schema_previous: JSON.stringify(previousSchemas)
+          // schema_previous: JSON.stringify(previousSchemas)
         }, {
           title: viewName
         });
@@ -1641,19 +1643,19 @@ export class GqlApiBuilder extends BaseApiBuilder<Noco> implements XcMetaMgr {
         const newSchemaa = GqlXcSchemaFactory.create(this.connectionConfig, this.generateRendererArgs(ctx)).getString();
 
         if (newSchemaa !== this.schemas[tn]) {
-          const oldModel = await this.xcMeta.metaGet(this.projectId, this.dbAlias, 'nc_models', {
-            title: tn
-          });
+          // const oldModel = await this.xcMeta.metaGet(this.projectId, this.dbAlias, 'nc_models', {
+          //   title: tn
+          // });
 
-          this.log(`onToggleModels : Updating and taking backup of schema for '%s'`, tn);
-          let previousSchemas = [this.schemas[tn]];
-          if (oldModel.schema_previous) {
-            previousSchemas = [...JSON.parse(oldModel.schema_previous), [this.schemas[tn]]].slice(-5);
-          }
+          // this.log(`onToggleModels : Updating and taking backup of schema for '%s'`, tn);
+          // let previousSchemas = [this.schemas[tn]];
+          // if (oldModel.schema_previous) {
+          //   previousSchemas = [...JSON.parse(oldModel.schema_previous), [this.schemas[tn]]].slice(-5);
+          // }
           this.schemas[tn] = newSchemaa;
           await this.xcMeta.metaUpdate(this.projectId, this.dbAlias, 'nc_models', {
             schema: this.schemas[tn],
-            schema_previous: JSON.stringify(previousSchemas)
+            // schema_previous: JSON.stringify(previousSchemas)
           }, {
             title: tn
           })
@@ -2019,19 +2021,19 @@ export class GqlApiBuilder extends BaseApiBuilder<Noco> implements XcMetaMgr {
     if (oldSchema !== this.schemas[tn]) {
       // this.log(`onTableUpdate :  Updating and taking backup of schema - '%s' table`, tn);
 
-      const oldModel = await this.xcMeta.metaGet(this.projectId, this.dbAlias, 'nc_models', {
-        title: tn
-      });
+      // const oldModel = await this.xcMeta.metaGet(this.projectId, this.dbAlias, 'nc_models', {
+      //   title: tn
+      // });
 
-      // keep upto 5 schema backup on table update
-      let previousSchemas = [oldSchema]
-      if (oldModel.schema_previous) {
-        previousSchemas = [...JSON.parse(oldModel.schema_previous), oldSchema].slice(-5);
-      }
+      // // keep upto 5 schema backup on table update
+      // let previousSchemas = [oldSchema]
+      // if (oldModel.schema_previous) {
+      //   previousSchemas = [...JSON.parse(oldModel.schema_previous), oldSchema].slice(-5);
+      // }
 
       await this.xcMeta.metaUpdate(this.projectId, this.dbAlias, 'nc_models', {
         schema: this.schemas[tn],
-        schema_previous: JSON.stringify(previousSchemas)
+        // schema_previous: JSON.stringify(previousSchemas)
       }, {
         title: tn,
         type: 'table'
diff --git a/packages/nocodb/src/lib/noco/meta/NcMetaMgr.ts b/packages/nocodb/src/lib/noco/meta/NcMetaMgr.ts
index 3e628a426f..a5b62da056 100644
--- a/packages/nocodb/src/lib/noco/meta/NcMetaMgr.ts
+++ b/packages/nocodb/src/lib/noco/meta/NcMetaMgr.ts
@@ -406,7 +406,7 @@ export default class NcMetaMgr {
       const projectDetails = projectDetailsJSON && JSON.parse(projectDetailsJSON);
 
       if (args.args.importsToCurrentProject) {
-        await promisify(ncp)(path.join(this.config.toolDir, 'uploads', 'nc', projectDetails.id), path.join(this.config.toolDir, 'nc', projectId), {clobber:true})
+        await promisify(ncp)(path.join(this.config.toolDir, 'uploads', 'nc', projectDetails.id), path.join(this.config.toolDir, 'nc', projectId), {clobber: true})
       } else {
         // decrypt with old key and encrypt again with latest key
         const projectConfig = JSON.parse(CryptoJS.AES.decrypt(projectDetails.config, projectDetails.key).toString(CryptoJS.enc.Utf8))
@@ -2413,6 +2413,7 @@ export default class NcMetaMgr {
   }
 
 
+  // todo: transaction
   protected async xcM2MRelationCreate(args: any, req): Promise<any> {
     const dbAlias = this.getDbAlias(args);
     const projectId = this.getProjectId(args);
@@ -2529,7 +2530,7 @@ export default class NcMetaMgr {
             }
           });
         }
-        const outrel1 = await this.projectMgr.getSqlMgr({id: projectId}).handleRequest('n', {
+        const outrel1 = await this.projectMgr.getSqlMgr({id: projectId}).handleRequest('relationCreate', {
           ...args,
           args: rel2Args
         });
@@ -2677,45 +2678,54 @@ export default class NcMetaMgr {
         const assocMeta = JSON.parse(assoc.meta);
         const rel1 = assocMeta.belongsTo.find(bt => bt.rtn === args.args.parentTable)
         const rel2 = assocMeta.belongsTo.find(bt => bt.rtn === args.args.childTable)
-        await this.xcRelationColumnDelete({
-          ...args,
-          args: {
-            parentTable: rel1.rtn,
-            parentColumn: rel1.rcn,
-            childTable: rel1.tn,
-            childColumn: rel1.cn,
-            foreignKeyName: rel1.fkn,
-            type: 'bt',
-          }
-        }, req, false)
-        await this.xcRelationColumnDelete({
-          ...args,
-          args: {
-            parentTable: rel2.rtn,
-            parentColumn: rel2.rcn,
-            childTable: rel2.tn,
-            childColumn: rel2.cn,
-            foreignKeyName: rel2.fkn,
-            type: 'bt',
-          }
-        }, req, false);
+        if (rel1) {
+          await this.xcRelationColumnDelete({
+            ...args,
+            args: {
+              parentTable: rel1.rtn,
+              parentColumn: rel1.rcn,
+              childTable: rel1.tn,
+              childColumn: rel1.cn,
+              foreignKeyName: rel1.fkn,
+              type: 'bt',
+            }
+          }, req, false)
+        }
+        if (rel2) {
+          await this.xcRelationColumnDelete({
+            ...args,
+            args: {
+              parentTable: rel2.rtn,
+              parentColumn: rel2.rcn,
+              childTable: rel2.tn,
+              childColumn: rel2.cn,
+              foreignKeyName: rel2.fkn,
+              type: 'bt',
+            }
+          }, req, false);
+        }
 
+        // ignore deleting table if it have more than 2 columns
+        if (assocMeta.columns.length === 2) {
 
-        const opArgs = {
-          ...args,
-          args: assocMeta,
-          api: 'tableDelete',
-          sqlOpPlus: true,
-        };
-        const out = await this.projectMgr.getSqlMgr({id: projectId}).handleRequest('tableDelete', opArgs);
 
-        if (this.listener) {
-          await this.listener({
-            req: opArgs,
-            res: out,
-            user: req.user,
-            ctx: {req}
-          });
+          const opArgs = {
+            ...args,
+            args: assocMeta,
+            api: 'tableDelete',
+            sqlOpPlus: true,
+          };
+
+          const out = await this.projectMgr.getSqlMgr({id: projectId}).handleRequest('tableDelete', opArgs);
+
+          if (this.listener) {
+            await this.listener({
+              req: opArgs,
+              res: out,
+              user: req.user,
+              ctx: {req}
+            });
+          }
         }
 
       }
diff --git a/packages/nocodb/src/lib/noco/rest/RestApiBuilder.ts b/packages/nocodb/src/lib/noco/rest/RestApiBuilder.ts
index 5d2a47ffc1..bde3054181 100644
--- a/packages/nocodb/src/lib/noco/rest/RestApiBuilder.ts
+++ b/packages/nocodb/src/lib/noco/rest/RestApiBuilder.ts
@@ -1473,17 +1473,17 @@ export class RestApiBuilder extends BaseApiBuilder<Noco> {
       });
       const oldSwaggerDoc = JSON.parse(meta.schema);
 
-      // keep upto 5 schema backup on table update
-      let previousSchemas = [oldSwaggerDoc]
-      if (meta.schema_previous) {
-        previousSchemas = [...JSON.parse(meta.schema_previous), oldSwaggerDoc].slice(-5);
-      }
+      // // keep upto 5 schema backup on table update
+      // let previousSchemas = [oldSwaggerDoc]
+      // if (meta.schema_previous) {
+      //   previousSchemas = [...JSON.parse(meta.schema_previous), oldSwaggerDoc].slice(-5);
+      // }
 
 
       oldSwaggerDoc.definitions = swaggerDoc.definitions;
       await this.xcMeta.metaUpdate(this.projectId, this.dbAlias, 'nc_models', {
         schema: JSON.stringify(oldSwaggerDoc),
-        schema_previous: JSON.stringify(previousSchemas)
+        // schema_previous: JSON.stringify(previousSchemas)
       }, {
         title: changeObj.tn,
         type: 'table'
@@ -1779,17 +1779,17 @@ export class RestApiBuilder extends BaseApiBuilder<Noco> {
     });
     const oldSwaggerDoc = JSON.parse(meta.schema);
 
-    // keep upto 5 schema backup on table update
-    let previousSchemas = [oldSwaggerDoc]
-    if (meta.schema_previous) {
-      previousSchemas = [...JSON.parse(meta.schema_previous), oldSwaggerDoc].slice(-5);
-    }
+    // // keep upto 5 schema backup on table update
+    // let previousSchemas = [oldSwaggerDoc]
+    // if (meta.schema_previous) {
+    //   previousSchemas = [...JSON.parse(meta.schema_previous), oldSwaggerDoc].slice(-5);
+    // }
 
 
     oldSwaggerDoc.definitions = swaggerDoc.definitions;
     await this.xcMeta.metaUpdate(this.projectId, this.dbAlias, 'nc_models', {
       schema: JSON.stringify(oldSwaggerDoc),
-      schema_previous: JSON.stringify(previousSchemas)
+      // schema_previous: JSON.stringify(previousSchemas)
     }, {
       title: tn,
       type: 'table'
@@ -1825,16 +1825,16 @@ export class RestApiBuilder extends BaseApiBuilder<Noco> {
       });
       const oldSwaggerDoc = JSON.parse(meta.schema);
 
-      // keep upto 5 schema backup on table update
-      let previousSchemas = [oldSwaggerDoc]
-      if (meta.schema_previous) {
-        previousSchemas = [...JSON.parse(meta.schema_previous), oldSwaggerDoc].slice(-5);
-      }
+      // // keep upto 5 schema backup on table update
+      // let previousSchemas = [oldSwaggerDoc]
+      // if (meta.schema_previous) {
+      //   previousSchemas = [...JSON.parse(meta.schema_previous), oldSwaggerDoc].slice(-5);
+      // }
 
       oldSwaggerDoc.definitions = swaggerDoc.definitions;
       await this.xcMeta.metaUpdate(this.projectId, this.dbAlias, 'nc_models', {
         schema: JSON.stringify(oldSwaggerDoc),
-        schema_previous: JSON.stringify(previousSchemas)
+        // schema_previous: JSON.stringify(previousSchemas)
       }, {
         title: metaObj.tn,
         type: 'table'