Fixing some issues with MySQL and dropping foreign key constrained columns.

packages/server/src/api/controllers/table/external.js

@@ -98,6 +98,7 @@ function generateManyLinkSchema(datasource, column, table, relatedTable) {
     _id: buildExternalTableId(datasource._id, jcTblName),
     name: jcTblName,
     primary: [primary, relatedPrimary],
+    constrained: [primary, relatedPrimary],
     schema: {
       [primary]: foreignKeyStructure(primary, {
         toTable: table.name,
@@ -210,6 +211,12 @@ exports.save = async function (ctx) {
         relationType
       )
       fkTable.schema[foreignKey] = foreignKeyStructure(foreignKey)
+      if (fkTable.constrained == null) {
+        fkTable.constrained = []
+      }
+      if (fkTable.constrained.indexOf(foreignKey) === -1) {
+        fkTable.constrained.push(foreignKey)
+      }
       // foreign key is in other table, need to save it to external
       if (fkTable._id !== table._id) {
         extraTablesToUpdate.push(fkTable)
@@ -234,6 +241,13 @@ exports.save = async function (ctx) {
     await makeTableRequest(datasource, op, extraTable, tables, oldExtraTable)
   }
 
+  // make sure the constrained list, all still exist
+  if (Array.isArray(tableToSave.constrained)) {
+    tableToSave.constrained = tableToSave.constrained.filter(constraint =>
+      Object.keys(tableToSave.schema).includes(constraint)
+    )
+  }
+
   // store it into couch now for budibase reference
   datasource.entities[tableToSave.name] = tableToSave
   await db.put(datasource)

packages/server/src/definitions/common.ts

@@ -46,6 +46,7 @@ export interface Table extends Base {
   schema: TableSchema
   primaryDisplay?: string
   sourceId?: string
+  constrained?: string[]
 }
 
 export interface Row extends Base {

packages/server/src/integrations/base/sqlTable.ts

@@ -19,6 +19,7 @@ function generateSchema(schema: CreateTableBuilder, table: Table, tables: Record
     schema.primary(metaCols.map(col => col.name))
   }
 
+
   // check if any columns need added
   const foreignKeys = Object.values(table.schema).map(col => col.foreignKey)
   for (let [key, column] of Object.entries(table.schema)) {
@@ -78,6 +79,9 @@ function generateSchema(schema: CreateTableBuilder, table: Table, tables: Record
       .filter(([key, schema]) => schema.type !== FieldTypes.LINK && table.schema[key] == null)
       .map(([key]) => key)
     deletedColumns.forEach(key => {
+      if (oldTable.constrained && oldTable.constrained.indexOf(key) !== -1) {
+        schema.dropForeign(key)
+      }
       schema.dropColumn(key)
     })
   }

packages/server/src/integrations/mysql.ts

@@ -265,7 +265,7 @@ module MySQLModule {
       if (Array.isArray(input)) {
         const responses = []
         for (let query of input) {
-          responses.push(await internalQuery(this.client, query))
+          responses.push(await internalQuery(this.client, query, false))
         }
         return responses
       }