feat: add DAY function support(PG)

packages/nocodb-sdk/src/lib/formulaHelpers.ts

@@ -396,6 +396,16 @@ const formulas: Record<string, FormulaMeta> = {
     examples: ['DATESTR({column1})'],
     returnType: FormulaDataTypes.STRING,
   },
+  DAY: {
+    validation: {
+      args: {
+        rqd: 1,
+      },
+    },
+    description: 'Formats a datetime into a string (YYYY-MM-DD)',
+    examples: ['DATESTR({column1})'],
+    returnType: FormulaDataTypes.STRING,
+  },
   DATETIME_DIFF: {
     validation: {
       args: {

packages/nocodb/src/db/functionMappings/pg.ts

@@ -139,7 +139,16 @@ const pg = {
       builder: knex.raw(
         `TO_DATE(${
           (await fn(pt?.arguments[0])).builder
-        }, 'YYYY-MM-DD') ${colAlias}`,
+        }, 'YYYY-MM-DD')::text ${colAlias}`,
+      ),
+    };
+  },
+  DAY: async ({ fn, knex, pt, colAlias }: MapFnArgs) => {
+    return {
+      builder: knex.raw(
+        `EXTRACT('Day' FROM DATE ${
+          (await fn(pt?.arguments[0])).builder
+        }) ${colAlias}`,
       ),
     };
   },