Real-time stacked-up coin counts with the help of Computer Vision using Python-based OpenCV.

Hi Guys,

Today, I’ll be using another exciting installment of Computer Vision. Today, our focus will be to get a sense of visual counting. Let me explain. This post will demonstrate how to count the number of stacked-up coins using computer vision. And, we’re going to add more coins to see the number changes.

Why don’t we see the demo first before jumping into the technical details?

Demo

Isn’t it exciting?


Architecture:

Let us understand the architecture –

From the above diagram, one can notice that as raw video feed captured from a specific location at a measured distance. The python-based intelligent application will read the numbers & project on top of the video feed for human validations.

Let me share one more perspective of how you can configure this experiment with another diagram that I prepared for this post.

Setup Process

From the above picture, one can see that a specific distance exists between the camera & the stacked coins as that will influence the single coin width.

You can see how that changed with the following pictures –

This entire test will depend upon many factors to consider to get effective results. I provided the basic demo. However, to make it robust & dynamic, one can dynamically diagnose the distance & individual coin width before starting this project. I felt that part should be machine learning to correctly predict the particular coin width depending upon the length & number of coins stacked. I leave it to you to explore that part.

Then how does the Aruco marker comes into the picture?

Let’s read it from the primary source side –

From: Source

Please refer to the following link if you want to know more.

For our use case, we’ll be using the following aruco marker –

Marker

How will this help us? Because we know the width & height of it. And depending upon the placement & overall pixel area size, our application can then identify the pixel to centimeter ratio & which will enable us to predict any other objects’ height & width. Once we have that, the application will divide that by the calculated width we observed for each coin from this distance. And, then the application will be able to predict the actual counts in real-time.

How can you identify the individual width?

My easy process would be to put ten quarter dollars stacked up & then you will get the height from the Computer vision. You have to divide that height by 10 to get the individual width of the coin until you build the model to predict the correct width depending upon the distance.


CODE:

Let us understand the code now –

  • clsConfig.py (Configuration file for the entire application.)


################################################
#### Written By: SATYAKI DE ####
#### Written On: 15-May-2020 ####
#### Modified On: 28-Dec-2021 ####
#### ####
#### Objective: This script is a config ####
#### file, contains all the keys for ####
#### Machine-Learning & streaming dashboard.####
#### ####
################################################
import os
import platform as pl
class clsConfig(object):
Curr_Path = os.path.dirname(os.path.realpath(__file__))
os_det = pl.system()
if os_det == "Windows":
sep = '\\'
else:
sep = '/'
conf = {
'APP_ID': 1,
'ARCH_DIR': Curr_Path + sep + 'arch' + sep,
'PROFILE_PATH': Curr_Path + sep + 'profile' + sep,
'LOG_PATH': Curr_Path + sep + 'log' + sep,
'REPORT_PATH': Curr_Path + sep + 'report',
'FILE_NAME': Curr_Path + sep + 'Image' + sep + 'Orig.jpeg',
'SRC_PATH': Curr_Path + sep + 'data' + sep,
'APP_DESC_1': 'Old Video Enhancement!',
'DEBUG_IND': 'N',
'INIT_PATH': Curr_Path,
'SUBDIR': 'data',
'SEP': sep,
'COIN_DEF_HEIGHT':0.22,
'PIC_TO_CM_MAP': 15.24,
'CONTOUR_AREA': 2000
}

view raw

clsConfig.py

hosted with ❤ by GitHub

'COIN_DEF_HEIGHT':0.22,
'PIC_TO_CM_MAP': 15.24,
'CONTOUR_AREA': 2000

The above entries are the important for us.

  1. PIC_TO_CM_MAP is the total length of the Aruco marker in centimeters involving all four sides.
  2. CONTOUR_AREA will change depending upon the minimum size you want to identify as part of the contour.
  3. COIN_DEF_HEIGHT needs to be revised as part of the previous steps explained.
  • clsAutoDetector.py (This python script will detect the contour.)


###############################################
#### Written By: SATYAKI DE ####
#### Written On: 17-Jan-2022 ####
#### Modified On 20-Mar-2022 ####
#### ####
#### Objective: This python script will ####
#### auto-detects the contours of an image ####
#### using grayscale conversion & then ####
#### share the contours details to the ####
#### calling class. ####
###############################################
import cv2
from clsConfig import clsConfig as cf
class clsAutoDetector():
def __init__(self):
self.cntArea = int(cf.conf['CONTOUR_AREA'])
def detectObjects(self, frame):
try:
cntArea = self.cntArea
# Convert Image to grayscale Image
grayImage = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
# Create a Mask with adaptive threshold
maskImage = cv2.adaptiveThreshold(grayImage, 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY_INV, 19, 5)
cv2.imshow("Masked-Image", maskImage)
# Find contours
conts, Oth = cv2.findContours(maskImage, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
objectsConts = []
for cnt in conts:
area = cv2.contourArea(cnt)
if area > cntArea:
objectsConts.append(cnt)
return objectsConts
except Exception as e:
x = str(e)
print('Error: ', x)
objectsConts = []
return objectsConts

Key snippets from the above script are as follows –

# Find contours
conts, Oth = cv2.findContours(maskImage, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)

objectsConts = []

for cnt in conts:
    area = cv2.contourArea(cnt)
    if area > cntArea:
        objectsConts.append(cnt)

Depending upon the supplied contour area, this script will identify & mark the contour of every frame captured through WebCam.

  • clsCountRealtime.py (This is the main class to calculate the number of stacked coins after reading using computer vision.)


##################################################
#### Written By: SATYAKI DE ####
#### Written On: 17-Jan-2022 ####
#### Modified On 20-Mar-2022 ####
#### ####
#### Objective: This python class will ####
#### learn the number of coins stacks on ####
#### top of another using computer vision ####
#### with the help from Open-CV after ####
#### manually recalibarting the initial ####
#### data (Individual Coin Heights needs to ####
#### adjust based on the distance of camera.) ####
##################################################
import cv2
from clsAutoDetector import *
import numpy as np
import os
import platform as pl
# Custom Class
from clsConfig import clsConfig as cf
import clsL as cl
# Initiating Log class
l = cl.clsL()
# Load Aruco detector
arucoParams = cv2.aruco.DetectorParameters_create()
arucoDict = cv2.aruco.Dictionary_get(cv2.aruco.DICT_5X5_50)
# Load Object Detector
detector = clsAutoDetector()
class clsCountRealtime:
def __init__(self):
self.sep = str(cf.conf['SEP'])
self.Curr_Path = str(cf.conf['INIT_PATH'])
self.coinDefH = float(cf.conf['COIN_DEF_HEIGHT'])
self.pics2cm = float(cf.conf['PIC_TO_CM_MAP'])
def learnStats(self, debugInd, var):
try:
# Per Coin Default Size from the known distance_to_camera
coinDefH = self.coinDefH
pics2cm = self.pics2cm
# Load Cap
cap = cv2.VideoCapture(0)
cap.set(cv2.CAP_PROP_FRAME_WIDTH, 1280)
cap.set(cv2.CAP_PROP_FRAME_HEIGHT, 720)
while True:
success, img = cap.read()
if success == False:
break
# Get Aruco marker
imgCorners, a, b = cv2.aruco.detectMarkers(img, arucoDict, parameters=arucoParams)
if imgCorners:
# Draw polygon around the marker
imgCornersInt = np.int0(imgCorners)
cv2.polylines(img, imgCornersInt, True, (0, 255, 0), 5)
# Aruco Perimeter
arucoPerimeter = cv2.arcLength(imgCornersInt[0], True)
# Pixel to cm ratio
pixelCMRatio = arucoPerimeter / pics2cm
contours = detector.detectObjects(img)
# Draw objects boundaries
for cnt in contours:
# Get rect
rect = cv2.boundingRect(cnt)
(x, y, w, h) = rect
print('*'*60)
print('Width Pixel: ')
print(str(w))
print('Height Pixel: ')
print(str(h))
# Get Width and Height of the Objects by applying the Ratio pixel to cm
objWidth = round(w / pixelCMRatio, 1)
objHeight = round(h / pixelCMRatio, 1)
cv2.rectangle(img, (x, y), (x + w, y + h), (255, 0, 0), 2)
cv2.putText(img, "Width {} cm".format(objWidth), (int(x – 100), int(y – 20)), cv2.FONT_HERSHEY_PLAIN, 2, (100, 200, 0), 2)
cv2.putText(img, "Height {} cm".format(objHeight), (int(x – 100), int(y + 15)), cv2.FONT_HERSHEY_PLAIN, 2, (100, 200, 0), 2)
NoOfCoins = round(objHeight / coinDefH)
cv2.putText(img, "No Of Coins: {}".format(NoOfCoins), (int(x – 100), int(y + 35)), cv2.FONT_HERSHEY_PLAIN, 2, (250, 0, 250), 2)
print('Final Height: ')
print(str(objHeight))
print('No Of Coins: ')
print(str(NoOfCoins))
cv2.imshow("Image", img)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
cap.release()
cv2.destroyAllWindows()
return 0
except Exception as e:
x = str(e)
print('Error: ', x)
return 1

Some of the key snippets from this script –

# Aruco Perimeter
arucoPerimeter = cv2.arcLength(imgCornersInt[0], True)

# Pixel to cm ratio
pixelCMRatio = arucoPerimeter / pics2cm

The above lines will extract the critical auroco perimeter & then the ratio between pixel against centimeters.

contours = detector.detectObjects(img)

The application detects the contours of each frame from the previous class, which will be used here.

# Draw objects boundaries
for cnt in contours:
    # Get rect
    rect = cv2.boundingRect(cnt)
    (x, y, w, h) = rect

In this step, the application will draw the object contours & also capture the center points, along with the height & width of the identified objects.

# Get Width and Height of the Objects by applying the Ratio pixel to cm
objWidth = round(w / pixelCMRatio, 1)
objHeight = round(h / pixelCMRatio, 1)

Finally, identify the width & height of the contoured object in centimeters.

cv2.putText(img, "Width {} cm".format(objWidth), (int(x - 100), int(y - 20)), cv2.FONT_HERSHEY_PLAIN, 2, (100, 200, 0), 2)
cv2.putText(img, "Height {} cm".format(objHeight), (int(x - 100), int(y + 15)), cv2.FONT_HERSHEY_PLAIN, 2, (100, 200, 0), 2)

NoOfCoins = round(objHeight / coinDefH)

cv2.putText(img, "No Of Coins: {}".format(NoOfCoins), (int(x - 100), int(y + 35)), cv2.FONT_HERSHEY_PLAIN, 2, (250, 0, 250), 2)

It displays both the height, width & total number of coins on top of the live video.

if cv2.waitKey(1) & 0xFF == ord('q'):
    break

The above line will help the developer exit from the visual application by pressing the escape or ‘q’ key in Macbook.

  • visualDataRead.py (Main calling function.)


###############################################
#### Written By: SATYAKI DE ####
#### Written On: 17-Jan-2022 ####
#### Modified On 20-Mar-2022 ####
#### ####
#### Objective: This is the main calling ####
#### python script that will invoke the ####
#### clsCountRealtime class to initiate ####
#### the model to read the real-time ####
#### stckaed-up coins & share the actual ####
#### numbers on top of the video feed. ####
###############################################
# We keep the setup code in a different class as shown below.
import clsCountRealtime as ar
from clsConfig import clsConfig as cf
import datetime
import logging
###############################################
### Global Section ###
###############################################
# Instantiating all the three classes
x1 = ar.clsCountRealtime()
###############################################
### End of Global Section ###
###############################################
def main():
try:
# Other useful variables
debugInd = 'Y'
var = datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
var1 = datetime.datetime.now()
print('Start Time: ', str(var))
# End of useful variables
# Initiating Log Class
general_log_path = str(cf.conf['LOG_PATH'])
# Enabling Logging Info
logging.basicConfig(filename=general_log_path + 'restoreVideo.log', level=logging.INFO)
print('Started Capturing Real-Time Coin Counts!')
# Execute all the pass
r1 = x1.learnStats(debugInd, var)
if (r1 == 0):
print('Successfully counts number of stcaked coins!')
else:
print('Failed to counts number of stcaked coins!')
var2 = datetime.datetime.now()
c = var2 var1
minutes = c.total_seconds() / 60
print('Total difference in minutes: ', str(minutes))
print('End Time: ', str(var1))
except Exception as e:
x = str(e)
print('Error: ', x)
if __name__ == "__main__":
main()

And, the key snippet from the above script –

x1 = ar.clsCountRealtime()

The application instantiates the main class.

# Execute all the pass
r1 = x1.learnStats(debugInd, var)

if (r1 == 0):
    print('Successfully counts number of stcaked coins!')
else:
    print('Failed to counts number of stcaked coins!')

The above code invokes the learnStats function to calculate the count of stacked coins.


FOLDER STRUCTURE:

Folder Details

So, we’ve done it.

You will get the complete codebase in the following Github link.

I’ll bring some more exciting topic in the coming days from the Python verse. Please share & subscribe my post & let me know your feedback.

Till then, Happy Avenging! 😀

Note: All the data & scenario posted here are representational data & scenarios & available over the internet & for educational purpose only. Some of the images (except my photo) that we’ve used are available over the net. We don’t claim the ownership of these images. There is an always room for improvement & especially the prediction quality.

Publishing new Python Library for JSON & NoSQL

Hi Guys!

As discussed,

Please find the link of the PyPI package of new enhanced JSON library on Python. This is particularly very useful as I’ve accommodated the following features into it.

  1. distinct
  2. nvl
  3. partition_by
  4. regex_like
  5. regex_replace
  6. regex_substr

All these functions can be used over JSON payload through python. I’ll discuss this in details in my next blog post.

However, I would like to suggest this library that will be handy for NoSQL databases like Cosmos DB. Now, you can quickly implement many of these features such as distinct, partitioning & regular expressions with less effort.

Please find the library URL.

Let me know your feedback on the same.

N.B.: I’ve tested this library both on Windows 10 & Ubuntu 18. And, the python version that I’ve used are Python3.6 & Python3.7.

Till then!

Happy Avenging!

String Manipulation Advanced Using Teradata 14.0 Regular Expression

Today, I’ll show couple of very useful functions or logic implemented in Teradata using It’s Regular Expression.

There is two very popular demand comes from most of the Developer across different databases regarding the following two cases –

1. How to Split Comma Separated Values in each rows 

2. How to bind separate values in 1 row (Just opposite of Step 1)

2nd Options are very demanding as Cross platform database professional specially Oracle Developers looking for these kind of implementation as Oracle has directly built-in functions to do the same. Those functions are Listagg, wm_concat, group_concat.

Let’s check the solution –

Case 1,

Let’s create the table & prepare some data –

 

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CREATE MULTISET TABLE ETL_DATA.PARSE_STR
  (
     SEQ_NO       INTEGER,
     SRC_STR     VARCHAR(70)
  );
 
CREATE TABLE completed. 0 rows processed. Elapsed Time =  00:00:01.864

 

Let’s insert some data –

 

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INSERT INTO ETL_DATA.PARSE_STR VALUES(1,'RAM,TRIDIB,ANUPAM,BIRESWAR,SUJAY')
;INSERT INTO ETL_DATA.PARSE_STR VALUES(2,'TUNKAI,SAYAN,BABU,PAPU')
;INSERT INTO ETL_DATA.PARSE_STR VALUES(3,'IK,ATBIS,SAPMUNDA');

 

Let’s check the value –

 

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SEQ_NO          SRC_STR
------  ----------------------------------
    1   RAM,TRIDIB,ANUPAM,BIRESWAR,SUJAY
    2   TUNKAI,SAYAN,BABU,PAPU
    3   IK,ATBIS,SAPMUNDA

 

Fine, Now our objective will be split these comma separated values in each lines.

 

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SELECT b.SEQ_NO,
       regexp_substr(b.SRC_STR,'[^,]+',1,day_of_calendar) AS SRC_STR
FROM sys_calendar.calendar ,
     PARSE_STR b
WHERE day_of_calendar BETWEEN 1 AND  (LENGTH(b.SRC_STR) - LENGTH(regexp_replace(b.SRC_STR,'[^A-Z]+','',1,0,'i'))+1 )
ORDER BY 1,2;

 

And, let’s check the output –

 

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SEQ_NO  SRC_STR
-----   ----------------------
1       ANUPAM
1       BIRESWAR
1       RAM
1       SUJAY
1       TRIDIB
2       BABU
2       PAPU
2       SAYAN
2       TUNKAI
3       ATBIS
3       IK
3       SAPMUNDA

 

Gr8! I guess, result is coming as per my expectation. 🙂

 

Case 2(Subsitute Of Listagg, wm_concat, group_concat in Oracle),

This we’ve to do it in Two small Steps for better understanding & performance.

First, let us create another table –

 

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CREATE MULTISET TABLE ETL_DATA.WM_CONCAT_TAB
   (
      SEQ_NO   INTEGER,
      SRC_STR VARCHAR(20)
   );
    
CREATE TABLE completed. 0 rows processed. Elapsed Time =  00:00:01.230

 

Good. Now we’ll populate some data into this table. We’ll populate data from Step 1 as this will provide the exact data that we’re expecting as input test data for Case 2.

Let’s insert those data –

 

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INSERT INTO ETL_DATA.WM_CONCAT_TAB
SELECT b.SEQ_NO,
       regexp_substr(b.SRC_STR,'[^,]+',1,day_of_calendar) AS SRC_STR
FROM sys_calendar.calendar ,
     PARSE_STR b
WHERE day_of_calendar BETWEEN 1 AND  (LENGTH(b.SRC_STR) - LENGTH(regexp_replace(b.SRC_STR,'[^A-Z]+','',1,0,'i'))+1 );

 

Let’s check the data –

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SEQ_NO  SRC_STR
------  --------------------
1       ANUPAM
1       BIRESWAR
1       RAM
1       SUJAY
1       TRIDIB
2       BABU
2       PAPU
2       SAYAN
2       TUNKAI
3       ATBIS
3       IK
3       SAPMUNDA

 

As you know in TD we’ve significant restcriction regarding Hirarchical Queries & Recursive Queries. So, In this step we’ll build one relationship like employee & manager in popular employee table. So, if we have that kind of relation then we can easily establish & fit that in TD model.

Let’s create this intermediate table. In this case we’ll go for mapping between current rows with next rows. This is also very useful process. In Oracle, they have LEAD or LAG functions to achieve the same. But, here we’ve to work a little bit more to achive the same.

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CREATE MULTISET VOLATILE TABLE VT_SRC_ARRNG
AS
     (
            SELECT SEQ_NO,
                   SRC_STR,
                   MAX(SRC_STR) OVER(
                                        PARTITION BY SEQ_NO
                                        ORDER BY SEQ_NO, SRC_STR
                                        ROWS BETWEEN 1 FOLLOWING AND 1 FOLLOWING 
                                    ) AS PREV_SRC_STR,
                   COUNT(*)  OVER(
                                    PARTITION BY SEQ_NO
                                 ) AS MAX_RECUR_CNT
            FROM WM_CONCAT_TAB
      )
WITH DATA
ON COMMIT
PRESERVE ROWS;
 
CREATE TABLE completed. 0 rows processed. Elapsed Time =  00:00:01.102

 

Let’s look the output –

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SELECT *
FROM VT_SRC_ARRNG
ORDER BY 1,2;
 
 
 
 
SEQ_NO  SRC_STR  PREV_SRC_STR    MAX_RECUR_CNT
-----   -------  --------------- ---------------------
1       ANUPAM      BIRESWAR     5
1       BIRESWAR    RAM          5
1       RAM         SUJAY        5
1       SUJAY       TRIDIB       5
1       TRIDIB      ?            5
2       BABU        PAPU         4
2       PAPU        SAYAN        4
2       SAYAN       TUNKAI       4
2       TUNKAI      ?            4
3       ATBIS       IK           3
3       IK          SAPMUNDA     3
3       SAPMUNDA    ?            3

 

Fine. From the above VT we can see every Source String has one Previous Source String. Also, we’ve noted down that in each window of SEQ_NO how many levels are there by MAX_RECUR_CNT. We’ll use this column later.

Let’s move to the 2nd & final part –

Let’s aggregate the values based on SEQ_NO & club them with comma –

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WITH RECURSIVE WM_CONCAT(SEQ_NO, SRC_STR, PREV_SRC_STR, MAX_RECUR_CNT, LVL,  COMMA_SEP_STR)
AS
     (
        SELECT SEQ_NO,
               SRC_STR,
               PREV_SRC_STR,
               MAX_RECUR_CNT,
               1 AS LVL,
               CAST( '' AS VARCHAR(100)) AS COMMA_SEP_STR
       FROM VT_SRC_ARRNG
       WHERE  PREV_SRC_STR IS NULL
       UNION ALL
       SELECT  b.SEQ_NO,
               b.SRC_STR,
               b.PREV_SRC_STR,
               b.MAX_RECUR_CNT,
               c.LVL+1 AS LVL,
               c.COMMA_SEP_STR||b.SRC_STR||',' AS COMMA_SEP_STR
       FROM VT_SRC_ARRNG b,
               WM_CONCAT c
       WHERE c.SRC_STR =  b.PREV_SRC_STR
     )
SELECT k.SEQ_NO,
       k.AGGR_STR
FROM (               
    SELECT SEQ_NO,
           SRC_STR,
           LVL,
           MAX_RECUR_CNT,
           MIN(CASE
                 WHEN LVL = 1 THEN
                    SRC_STR
               ELSE
                  'ZZZZZ'
               END   ) OVER(
                                 PARTITION BY SEQ_NO
                                 ORDER BY LVL ASC
                           ) ROOT_SRC_STR,
           COMMA_SEP_STR||ROOT_SRC_STR AS AGGR_STR
    FROM WM_CONCAT
    )  k
WHERE k.LVL = k.MAX_RECUR_CNT
ORDER BY 1,2;

 

Let’s check the output –

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SEQ_NO  AGGR_STR
------- ---------------------------
1       SUJAY,RAM,BIRESWAR,ANUPAM,TRIDIB
2       SAYAN,PAPU,BABU,TUNKAI
3       IK,ATBIS,SAPMUNDA

 

I guess, We’ve done it. 😀

So, You can achieve the same without writing any UDF.

 

Ref Cursor In SQL

There are number occasions, which i personally met when many of my juniors are looking for solution of using ref-cursor in SQL based on some certain requirement and they want to use it in SQL that can be embed into some JAVA based applications. I’ve looked into that and able to produce one such useful case which can handy (Though i’ll prefer different approach than this.) when i require this kind of work.

satyaki>
satyaki>select * from v$version;

BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod
PL/SQL Release 10.2.0.1.0 - Production
CORE 10.2.0.1.0 Production
TNS for Linux: Version 10.2.0.1.0 - Production
NLSRTL Version 10.2.0.1.0 - Production

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>create table t_emp
2 as
3 select empno,
4 ename,
5 mgr,
6 sal
7 from emp
8 where 1=2;

Table created.

Elapsed: 00:00:00.05
satyaki>
satyaki>set lin 80
satyaki>
satyaki>desc t_emp;
Name Null? Type
----------------------------------------- -------- ----------------------
EMPNO NUMBER(4)
ENAME VARCHAR2(10)
MGR NUMBER(4)
SAL NUMBER(7,2)

satyaki>
satyaki>
satyaki>set lin 310
satyaki>
satyaki>select * from t_emp;

no rows selected

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>create or replace type etype as object
2 (
3 empno number,
4 ename varchar2(10),
5 mgr number,
6 sal number
7 );
8 /

Type created.

Elapsed: 00:00:01.03
satyaki>
satyaki>create or replace type t_etype as table of etype;
2 /

Type created.

Elapsed: 00:00:00.02
satyaki>
satyaki>create or replace function get_dept_emps(p_deptno in number)
2 return sys_refcursor
3 is
4 v_rc sys_refcursor;
5 begin
6 open v_rc for 'select empno, ename, mgr, sal from emp where deptno = :deptno' using p_deptno;
7 return v_rc;
8 end;
9 /

Function created.

Elapsed: 00:00:00.05
satyaki>
satyaki>
satyaki>create or replace function fetch_emps(deptno in number := null)
2 return t_etype
3 is
4 v_emptype t_etype := t_etype(); -- Declare a local table structure and initialize it
5 v_cnt number := 0;
6 v_rc sys_refcursor;
7 v_empno number;
8 v_ename varchar2(10);
9 v_mgr number;
10 v_sal number;
11 begin
12 v_rc := get_dept_emps(deptno);
13 loop
14 fetch v_rc into v_empno, v_ename, v_mgr, v_sal;
15 exit when v_rc%NOTFOUND;
16 v_emptype.extend;
17 v_cnt := v_cnt + 1;
18 v_emptype(v_cnt) := etype(v_empno, v_ename, v_mgr, v_sal);
19 end loop;
20 close v_rc;
21 return v_emptype;
22 end;
23 /

Function created.

Elapsed: 00:00:00.06
satyaki>
satyaki>
satyaki>select * from t_emp;

no rows selected

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>
satyaki>select * from t_emp;

no rows selected

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>insert into t_emp
2 select *
3 from table(fetch_emps(30));

4 rows created.

Elapsed: 00:00:00.02
satyaki>
satyaki>select * from t_emp;

EMPNO ENAME MGR SAL
---------- ---------- ---------- ----------
7654 MARTIN 7698 1815
7844 TURNER 7698 2178
7900 JAMES 7698 1379.4
7599 BILLY 7566 4500

Elapsed: 00:00:00.00
satyaki>
satyaki>commit;

Commit complete.

Elapsed: 00:00:00.00
satyaki>