what does sha() in mysql

SHA(string)
we can use it with sha1(string).
This function returns the Secure Hash Algorithm (SHA) 160-bit checksum for the given
string. The result is a string composed of 40 hexadecimal digits. NULL is returned if the
given string is NULL.

mysql statements

SYSTEM_USER( )

It’s synonymous with SESSION_USER( ) and USER( ).
This function returns the username
and the hostname for the current MySQL connection.
The function takes no arguments.

Normally used mysql statements list:
ALTER DATABASE, ALTER SCHEMA, ALTER SERVER, ALTER TABLE,
ALTER VIEW, CREATE DATABASE,CREATE INDEX, CREATE SCHEMA,
CREATE SERVER, CREATE TABLE, CREATE VIEW,DESCRIBE, DROP DATABASE, DROP INDEX, DROP SERVER, DROP TABLE, DROP VIEW, RENAME
DATABASE, RENAME TABLE, SHOW CHARACTER SET, SHOW COLLATION,
SHOW COLUMNS, SHOW CREATE DATABASE, SHOW CREATE TABLE,
SHOW CREATE VIEW, SHOW DATABASES, SHOW INDEXES,SHOW SCHEMAS
Data Manipulation Statements
Here is a list of SQL statements and clauses used in MySQL for data manipulation:
DELETE, DO, EXPLAIN, HANDLER, HELP, INSERT, JOIN, LIMIT, LOAD DATA INFILE, REPLACE,
SELECT, SET, SHOW ERRORS, SHOW WARNINGS, TRUNCATE, UNION, UPDATE, USE.
SHOW TABLE STATUS, SHOW TABLES, SHOW VIEWS.

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