Merge pull request #1433 from finn-auto/fix-distinct-endpoint

fix distinct api enpoint

packages/nocodb/src/lib/dataMapper/lib/BaseModel.ts

@@ -924,10 +924,18 @@ abstract class BaseModel {
    * @memberof BaseModel
    * @throws {Error}
    */
-  async distinct({ cn, fields = '', where, limit, offset, sort, condition }) {
+  async distinct({
+    column_name,
+    fields = '',
+    where,
+    limit,
+    offset,
+    sort,
+    condition
+  }) {
     try {
       const query = this.$db;
-      query.distinct(cn, ...fields.split(',').filter(Boolean));
+      query.distinct(column_name, ...fields.split(',').filter(Boolean));
       query.xwhere(where).condition(condition);
       this._paginateAndSort(query, { limit, offset, sort });
       return await this._run(query);

packages/nocodb/src/lib/dataMapper/lib/sql/BaseModelSql.ts

@@ -1205,8 +1205,7 @@ class BaseModelSql extends BaseModel {
    * @throws {Error}
    */
   async distinct({
-    cn,
-    fields = '',
+    column_name,
     where,
     limit,
     offset,
@@ -1214,9 +1213,8 @@ class BaseModelSql extends BaseModel {
     conditionGraph = null
   }) {
     try {
-      const query = this.$db;
-      query.distinct(
-        this.selectQuery([cn, ...fields.split(',').filter(Boolean)].join(','))
+      const query = this._buildDistinctQuery(
+        column_name ? column_name.split(',') : []
       );
       query.xwhere(where, this.selectQuery('')).conditionGraph(conditionGraph);
       this._paginateAndSort(query, { limit, offset, sort });
@@ -1227,6 +1225,64 @@ class BaseModelSql extends BaseModel {
     }
   }
 
+  /**
+   * Builds a query string that will return distinct values for the given column
+   * @param {string[]} columns - the column to query for distinct values
+   * @returns {object} the query.
+   */
+  private _buildDistinctQuery(columns: string[]) {
+    const query = this.$db;
+    const formulaColumns = this.filterFormulaColumns(columns);
+    const otherColumns = _.difference(columns, formulaColumns);
+    if (!otherColumns.length && !formulaColumns.length) {
+      query.distinct(this.selectQuery('')).distinct(...this.selectFormulas);
+    }
+    if (otherColumns.length) {
+      query.distinct(this.selectQuery(otherColumns.join(',')));
+    }
+    if (formulaColumns.length) {
+      query.distinct(...this.selectFormulasForColumns(formulaColumns));
+    }
+    return query;
+  }
+
+  /**
+   * Selects the formulas for the give columns.
+   * @param {Array} sheet - The colums to select formulas for.
+   * @returns Array of formulas.
+   */
+  private selectFormulasForColumns(columns: string[]) {
+    return (this.virtualColumns || [])?.reduce((arr, v) => {
+      if (
+        v.formula?.value &&
+        !v.formula?.error?.length &&
+        columns.includes(v._cn)
+      ) {
+        arr.push(
+          formulaQueryBuilder(
+            v.formula?.tree,
+            v._cn,
+            this.dbDriver,
+            this.aliasToColumn
+          )
+        );
+      }
+      return arr;
+    }, []);
+  }
+
+  /**
+   * Returns an array of the columns that are of formula type.
+   * @returns {Array<string>} - an array of the formula columns.
+   */
+  private filterFormulaColumns(columns: string[]) {
+    return columns.filter(column => {
+      return this.virtualColumns.find(
+        col => col._cn === column && col?.formula
+      );
+    });
+  }
+
   /**
    * Runs raw query on database
    *