MySQL User Permissions and Database Queries

Posted by on Jan 12, 2025 in Computing and Communications | 0 comments

Specific Queries and User Management

A specific query that shows global users who have permission to grant on all tables of the ‘jmmusuarios’ database:

CREATE USER 'globalnoconcede'@'localhost' IDENTIFIED BY 'soyglobal';
GRANT ALL PRIVILEGES ON JMMUSUARIOS.* TO 'globalnoconcede'@'localhost';

SELECT DB.User, DB.Db, DB.Grant_priv
FROM MYSQL.DB
WHERE DB.Db LIKE 'jmmusuarios'
AND DB.Grant_Priv LIKE 'Y';

Query that shows the functions and procedures in the system:

DESCRIBE MYSQL.PROC;

SELECT PROC.name, PROC.

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SQL Queries and PL/SQL Functions Examples

Posted by on Jan 10, 2025 in Computing and Communications | 0 comments

SQL Queries

Find series name by episode:

SELECT s.nombre "NOMBRE SERIE"
FROM SERIE s
WHERE s.ID_CODSERIE = (
  SELECT e.SERIE_ID_CODSERIE
  FROM EPISODIO e
  WHERE e.NOMBRE = 'la manzana madura'
);

Find actor name by character:

SELECT a.nombre "NOMBRE ACTOR"
FROM actor a
WHERE a.ID_ACTOR = (
  SELECT p.ACTOR_ID_ACTOR
  FROM personaje p
  WHERE p.NOMBRE = 'Sheldon'
);

Find actors who won a Grammy:

SELECT a.NOMBRE "NOMBRE ACTOR", a.F_NAC "FECHA DE NACIMIENTO"
FROM ACTOR a
INNER JOIN GANA g ON a.ID_ACTOR
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Oracle Database Architecture: Components and Structure

Posted by on Jan 10, 2025 in Computing and Communications | 0 comments

Key Components of an Oracle Database

  • Control File: Contains information about physical files, the name of the database, block sizes, and information for recovery. Control files are required to open the database.
  • Data File: Contains information that records end-user applications.
  • Redo Log: Records all changes made to the database and the recovery status.
  • Pfile and Spfile: These are settings of the System Global Area (SGA) and optional features of Oracle background processes.

Oracle Instance and Server

  • An
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Understanding Isometries in R2 and R3: A Comprehensive Breakdown

Posted by on Jan 10, 2025 in Computing and Communications | 0 comments

Understanding Isometries in R2

Theory

It retains the standard distance i = A · AT = Id. Det = +1 or -1.

Vector fix: v ∈ P associates at v ∈ P 1SI F ∈ G = Tv, then F o G also. Det H = Det G · Det F.

Equations: Tv(x, y) = (x, y). Base service: Tv = Cne · Tn · Cne-1

Note: A * I must be symmetrical.

CNE

  1. Find a point on the axis or plane (one that satisfies the equation).
  2. From the equation equal to 0, if you are caught, separate subjects. If not equal to 0, they are roofed and left all depending on
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