From 66a32254648268c7f8b2b99c23bdad18514fa1bd Mon Sep 17 00:00:00 2001
From: David Kiania <kianiadee@gmail.com>
Date: Thu, 26 Mar 2026 11:26:16 +0300
Subject: [PATCH] Adding the last of the Casting Lesson

---
 .DS_Store                        | Bin 8196 -> 8196 bytes
 Lessons/1.20/1.20_Data_types.sql |  80 +++++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+)
 create mode 100644 Lessons/1.20/1.20_Data_types.sql

diff --git a/.DS_Store b/.DS_Store
index 1b7efac776c9c981be23217b4659fbf3b161af6a..a750c5f5b17a0fd4964fa06ca053f2ffc866e8bf 100644
GIT binary patch
delta 223
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L;MvSB@s}L{E9gME

delta 223
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zVHlj8pIZRb!@$7!fnl<kpxop|0#<D9?8nx9TQONgP(dg+A7KVWc(aIL8xvEg`Q$mm
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MEa2J9F7cNg00LA?8~^|S

diff --git a/Lessons/1.20/1.20_Data_types.sql b/Lessons/1.20/1.20_Data_types.sql
new file mode 100644
index 0000000..633823e
--- /dev/null
+++ b/Lessons/1.20/1.20_Data_types.sql
@@ -0,0 +1,80 @@
+SELECT 
+* 
+FROM information_schema.columns;
+
+SELECT 
+    table_name,
+    column_name,
+    data_type
+FROM information_schema.columns
+WHERE table_name = 'job_postings_fact';
+
+DESCRIBE job_postings_fact;
+
+DESCRIBE
+SELECT 
+    job_title_short,
+    salary_year_avg
+FROM job_postings_fact;
+
+DESCRIBE
+SELECT 
+*
+FROM job_postings_fact;
+
+SELECT CAST ('2023-4-20' AS DATE);
+
+SELECT 
+    job_id,
+    CAST(job_work_from_home AS INT) AS job_work_from_home,
+    CAST(job_posted_date AS DATE) AS job_posted_date,
+    CAST(salary_year_avg AS DECIMAL(10,0)),
+FROM 
+    job_postings_fact
+WHERE salary_year_avg IS NOT NULL
+ORDER BY salary_year_avg DESC
+LIMIT 15;
+
+-- SELECT 
+--     job_id,
+--     CAST(job_work_from_home AS INT) AS job_work_from_home,
+--     CAST(job_posted_date AS DATE) AS job_posted_date,
+--     CAST(MAX(salary_year_avg) AS DECIMAL(10,0)) AS salary_year_avg
+-- FROM 
+--     job_postings_fact
+-- WHERE 
+--     salary_year_avg IS NOT NULL
+-- GROUP BY 
+--     job_id, job_work_from_home, job_posted_date
+-- ORDER BY 
+--     salary_year_avg DESC
+-- LIMIT 15;
+
+SELECT 
+    CAST(job_id AS VARCHAR) || '-' || CAST(company_id AS VARCHAR),
+    CAST(job_work_from_home AS INT) AS job_work_from_home,
+    CAST(job_posted_date AS DATE) AS job_posted_date,
+    CAST(salary_year_avg AS DECIMAL(10,0)),
+FROM 
+    job_postings_fact
+WHERE salary_year_avg IS NOT NULL
+LIMIT 15; 
+
+
+SELECT 
+    job_id::VARCHAR|| '-' ||company_id::VARCHAR AS id,
+    job_work_from_home::INT AS job_work_from_home,
+    job_posted_date::DATE AS job_posted_date,
+    salary_year_avg::DECIMAL(10,0) AS salary_year_avg,
+FROM 
+    job_postings_fact
+WHERE salary_year_avg IS NOT NULL
+LIMIT 15;
+
+
+SELECT *
+FROM job_postings_fact
+LIMIT 100;
+
+
+