diff --git a/pos-frontend/__test__/db.test.jsx b/pos-frontend/__test__/db.test.jsx
index fb6348a..ff296cf 100644
--- a/pos-frontend/__test__/db.test.jsx
+++ b/pos-frontend/__test__/db.test.jsx
@@ -11,7 +11,7 @@ describe('DATABASE', () => {
     let res = create_csv_database('csv_db/x.csv')
     print_head(res)
 
-    add_row(res, { "key": ["x"], "value": ["y"] })
+    add_row(res, { "a_key": ["x"], "a_value": ["y"] })
     print_head(res)
 
     save_db(res)
diff --git a/pos-frontend/__test__/rocksdb.test.jsx b/pos-frontend/__test__/rocks.test.jsx
similarity index 100%
rename from pos-frontend/__test__/rocksdb.test.jsx
rename to pos-frontend/__test__/rocks.test.jsx
diff --git a/pos-frontend/app/database.ts b/pos-frontend/app/database.ts
index da3b5b7..a597025 100644
--- a/pos-frontend/app/database.ts
+++ b/pos-frontend/app/database.ts
@@ -11,54 +11,6 @@ export function test_x(params: any) {
   let df = pl.readCSV("data/iris.csv")
 }
 
-class CSVDatabase {
-  private df: DataFrame | null = null
-  private filePath: string
-
-  constructor(filePath: string) {
-    this.filePath = filePath
-    this.loadCSV()
-  }
-
-  private loadCSV() {
-    fs.existsSync(this.filePath) ? this.df = pl.readCSV(this.filePath) : this.df = DataFrame([])
-  }
-
-  private saveCSV() {
-    if (this.df) {
-      fs.writeFileSync(this.filePath, this.df.writeCSV())
-    }
-  }
-
-  create(row: Record<string, any>) {
-    if (this.df) {
-      this.df = this.df.vstack(DataFrame([row]))
-      this.saveCSV()
-    }
-  }
-
-  read(filter: Record<string, any>) {
-    return this.df ? this.df.filter(filter) : null
-  }
-
-  update(filter: Record<string, any>, values: Record<string, any>) {
-    if (this.df) {
-      // update it
-      this.saveCSV()
-    }
-  }
-
-  delete(filter: Record<string, any>) {
-    if (this.df) {
-      // should be filter Not
-      this.df = this.df.filter(filter)
-      this.saveCSV()
-    }
-  }
-}
-
-// A CSV can refer to other CSV's via pointers, a type of metadata
-
 interface CSVDatabase2 {
   df: DataFrame
   filepath: string
@@ -66,7 +18,7 @@ interface CSVDatabase2 {
 
 export function create_csv_database(filepath: string): CSVDatabase2 {
   // let df = DataFrame([], { columns: ["key", "value"] })
-  let df = DataFrame({ "key": ['header'], "value": ['next'] })
+  let df = DataFrame({ 'a_key': ['1'], 'a_value': ['2'] })
 
   // writeFile(filepath, 'key,value\nheader,next', () => { })
   // let df = pl.readCSV(filepath)
@@ -79,8 +31,9 @@ export function save_db(db: CSVDatabase2) {
   db.df.writeCSV(db.filepath)
 }
 
-export function add_row(db: CSVDatabase2, row: Record<string, string>) {
-  db.df = db.df.vstack(DataFrame(row))
+export function add_row(db: CSVDatabase2, row: any) {
+  let d = DataFrame(row)
+  db.df = db.df.vstack(d)
 }
 
 export function print_head(db: CSVDatabase2) {
@@ -89,8 +42,27 @@ export function print_head(db: CSVDatabase2) {
 
 // can filter everything that is not the row, and do to db
 
-export function delete_row_by_key({df, filepath}: CSVDatabase2, key: string) {
+export function delete_row_by_key__({ df, filepath }: CSVDatabase2, key: string) {
   // db.df.drop(pl.col("key").eq(key))
   // df = df.select((pl.col("key") != key).alias("nrs > 1"))
   // db.df = db.df.filter(pl.col("key").neq(key))
 }
+
+export function delete_row_by_key(db: CSVDatabase2, key: string) {
+  console.log("NEXT COLUMNS")
+  console.log(db.df.columns)
+  db.df = db.df.filter(pl.col('a_key').neq(pl.lit(key)))
+}
+
+export function select_columns(db: CSVDatabase2, columns: string[]): DataFrame {
+  return db.df.select(...columns)
+}
+
+export function join_dataframes(db1: CSVDatabase2, db2: CSVDatabase2, on: string): DataFrame {
+  return db1.df.join(db2.df, { on, how: "inner" }) // or "left", "right", "outer"
+}
+
+export function add_simple_index(db: CSVDatabase2) {
+  const indices = Array.from(Array(db.df.height).keys()) // Create 0-N index
+  db.df = db.df.withColumn(pl.Series("index", indices))
+}
diff --git a/pos-frontend/csv_db/x.csv b/pos-frontend/csv_db/x.csv
index ca11190..b4e3165 100644
--- a/pos-frontend/csv_db/x.csv
+++ b/pos-frontend/csv_db/x.csv
@@ -1,3 +1,3 @@
-key,value
-header,next
+a_key,a_value
+1,2
 x,y