fix: item-batch validation

backend/database/bespoke.ts

@@ -132,6 +132,26 @@ export class BespokeQueries {
     `);
   }
 
+  static async itemHasTransactions(
+    db: DatabaseCore,
+    item: string
+  ): Promise<boolean> {
+  /*
+    * to check if an item of given name is present in the SLE
+    * taking the count of items from SLE which has the given item name
+    * if the count is greater than 0 considers item exists in SLE, returns true 
+    * if the count is lesser than 0 considers item does not exist in SLE, returns false
+  */
+    const query = db.knex!(ModelNameEnum.StockLedgerEntry)
+      .select('item')
+      .where('item', item);
+
+    const value = (await query) as Record<string, string | null>[];
+
+    if (!value) return false;
+    return true;
+  }
+
   static async getStockQuantity(
     db: DatabaseCore,
     item: string,
@@ -167,6 +187,4 @@ export class BespokeQueries {
 
     return value[0][Object.keys(value[0])[0]];
   }
-}
-
-// 
+}