Desc & Show Tables

Duration: 3 min

This video lesson is available to enrolled students.

Return to /learn/AMCAT-PREPARATION/sql-technical/sql/ddl-dml-dcl-tcl-desc/asset-desc-show-tables after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. Quantitative Ability: Percentage, Profit and Loss, Ratio and Proportion (Ratios), Average, Time and Work, Speed Time and Distance, Simple Interest and Compound Interest, Age Problems, Number System, Divisibility Rules, HCF LCM, Algebra, Permutation and Combination, Probability, Data Interpretation, Logarithm, Sequence and Series (Series), Powers and Exponents (Surds and Indices), Speed Mathematics and Basic Mathematics
  2. Logical Reasoning: Seating Arrangements, Puzzle Solving (Puzzles), Data Arrangement, Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Data Sufficiency, Venn Diagram, Inequality, Series (Number and Letter Series) (Numerical Relations and Reasoning), Logical Sequence Of Words, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning)
  3. Verbal Ability: Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Subject Verb Agreement (Verb Noun Agreement), Tenses, Articles, Preposition, Conjunction, Modals, Active Passive Voice (Voice), Direct and Indirect Speech, Vocabulary, Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Completion (Fill in the blanks), Sentence Correction (Error Correction), Cloze Test (Cloze Passage), Facts, Inference and Judgements
  4. Programming Fundamentals (Technical): C Fundamentals
  5. Data Structures (Technical): Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  6. Algorithms (Technical): Algorithm Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Time Complexity Analysis, Advanced Algorithms
  7. OOPs (Technical): Object Oriented Programming (OOPS)
  8. DBMS (Technical): Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, ORDBMS, Database Security & Authorization, Query Processing & Optimization, Enhanced Data Models, Data Warehousing & Mining, Big Data Systems, NoSQL
  9. SQL (Technical): SQL
  10. Operating Systems (Technical): Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS, Linux OS, Security, Distributed Systems, Virtual Machines
  11. Computer Networks (Technical): Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security, Mobile Technology, Cloud Computing and IoT, Cyber and Info Security
  12. Software Engineering (Technical): Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  13. Coding/Automata Round: Coding Questions by Yash Sir, C Programming by Yash Sir, Programming in C++, Java, Python for Placements by Yash Sir, Pseudo Codes
  14. Personality / Behavioral Assessment: Behavioral Assessment (Behavioral Competency Profiling) (Psychometric Test)
  15. Writing Assessment: English Writing Ability
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video is a lecture on SQL commands for database management, focusing on the DESCRIBE and SHOW TABLES commands. The first segment explains the DESCRIBE command, which acts as an 'X-ray' to inspect a table's structure. It details the command's syntax, `DESCRIBE table_name;`, and shows an example output for a 'Student' table, breaking down the columns: Field (column name), Type (data type), Null (whether NULL values are allowed), Key (indexing/primary key info), Default (default value), and Extra (additional info). The lecture also compares it to other commands: `SHOW TABLES` lists all tables in a database, and `SELECT * FROM table` displays the actual data. The second segment transitions to the SHOW TABLES command, explaining that in RDBMS like Oracle, it is not a direct command but is implemented using system views. It presents a table comparing three purposes: listing personal tables, accessible tables, and system-wide tables, each with its corresponding SQL query using `SELECT table_name FROM` and the appropriate system view (e.g., `user_tables`, `all_tables`, `dba_tables`). The lecturer emphasizes that Oracle uses these views instead of a direct SHOW TABLES command, unlike MySQL.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video begins with a slide titled 'DESCRIBE Command'. The lecturer explains that this command is used to check a table's column names, data types, and constraints before writing complex queries. The syntax is shown as `DESCRIBE table_name;`. An example output for a 'Student' table is displayed, showing columns for Field, Type, Null, Key, Default, and Extra. The lecturer explains what each column reveals: Field is the column name, Type is the data type (e.g., int, varchar), Null indicates if the column allows NULL values, Key identifies indexing or primary key information (e.g., PRI for Primary Key), and Default shows the default value if none is provided. The slide also includes a table comparing the DESCRIBE command with SHOW TABLES and SELECT * FROM commands, outlining their purposes and what they display.

  2. 2:00 – 3:16 02:00-03:16

    The video transitions to a new slide titled 'Show Tables Command'. The lecturer explains that in RDBMS like Oracle, the SHOW TABLES operation is not a direct command but is implemented using system views. The slide presents a table with three purposes: listing Personal Tables, Accessible Tables, and System-Wide (DBA) tables. For each purpose, it provides the syntax pattern (`SELECT table_name FROM`), the actual command (e.g., `SELECT table_name FROM user_tables;`), and what it shows. The lecturer explains that `user_tables` shows only tables created by the user, `all_tables` shows tables the user has access to, and `dba_tables` shows every table in the database, requiring DBA privileges. The lecturer uses a red pen to circle and emphasize key parts of the text and code on the slide.

The lecture progresses from a fundamental command for inspecting table structure (DESCRIBE) to a command for listing tables (SHOW TABLES), highlighting a key difference in implementation between database systems. It teaches that DESCRIBE provides a detailed blueprint of a single table, while SHOW TABLES provides a list of tables. The core synthesis is that while MySQL has a direct SHOW TABLES command, Oracle uses system views like `user_tables`, `all_tables`, and `dba_tables` to achieve the same result, with the scope of the list determined by the user's privileges. This demonstrates the importance of understanding the specific syntax and system architecture of the RDBMS being used.

Loading lesson…