Merge 79d446245e into 88e5be6e4b

fix spelling and whitespace in cheatsheets

databases/mysql.sh

@@ -16,3 +16,69 @@ GRANT ALL PRIVILEGES ON prospectwith.* TO 'power'@'localhost' WITH GRANT OPTION;
 CREATE USER 'newuser'@'localhost' IDENTIFIED BY 'password'; # Create user
 
 mysql -u root -pmypassword -e "MY SQL QUERY" &>> query.log & disown # Run SQL query in the background
+
+# *****************************************************************************
+# Database and Table Operations
+# *****************************************************************************
+
+CREATE DATABASE database_name; # Create a new database
+DROP DATABASE database_name; # Delete a database
+CREATE TABLE table_name (column1 datatype, column2 datatype, ...); # Create a new table
+DROP TABLE table_name; # Delete a table
+SHOW TABLES; # Display all tables in the current database
+DESCRIBE table_name; # Show the structure of a table
+
+# *****************************************************************************
+# Data Manipulation
+# *****************************************************************************
+
+INSERT INTO table_name (column1, column2, ...) VALUES (value1, value2, ...); # Insert data into a table
+UPDATE table_name SET column1 = value1, column2 = value2, ... WHERE condition; # Update existing data in a table
+DELETE FROM table_name WHERE condition; # Delete data from a table
+SELECT column1, column2, ... FROM table_name WHERE condition; # Select data from a table
+
+# *****************************************************************************
+# Backup and Restore
+# *****************************************************************************
+
+mysqldump -u username -p database_name table1 table2 > file.sql # Backup specific tables
+mysql -u username -p database_name < file.sql # Restore specific tables
+
+# *****************************************************************************
+# User Management and Security
+# *****************************************************************************
+
+REVOKE privilege_type ON database_name.table_name FROM 'username'@'hostname'; # Revoke privileges from a user
+DROP USER 'username'@'hostname'; # Delete a user
+ALTER USER 'username'@'hostname' IDENTIFIED BY 'newpassword'; # Reset a user's password
+
+# *****************************************************************************
+# Performance and Maintenance
+# *****************************************************************************
+
+OPTIMIZE TABLE table_name; # Optimize a table
+ANALYZE TABLE table_name; # Analyze a table for key distribution and storage optimization
+CHECK TABLE table_name; # Check a table for errors
+REPAIR TABLE table_name; # Repair a corrupted table
+
+# *****************************************************************************
+# Advanced Queries
+# *****************************************************************************
+
+SELECT ... FROM table1 JOIN table2 ON table1.column = table2.column; # Perform a join operation between two tables
+SELECT ... FROM (SELECT ... FROM table_name) AS subquery; # Use a subquery within another query
+SELECT column, COUNT(*) FROM table_name GROUP BY column; # Group results and use aggregate functions
+
+# *****************************************************************************
+# System Information
+# *****************************************************************************
+
+SELECT VERSION(); # Show the current version of MySQL
+SELECT User, Host FROM mysql.user; # List all current MySQL users
+
+# *****************************************************************************
+# Miscellaneous
+# *****************************************************************************
+
+SET GLOBAL general_log = 'ON'; # Enable query logging
+SHOW FULL PROCESSLIST; # Show the last queries executed in MySQL

languages/C#.txt

@@ -88,7 +88,7 @@ CHEATSHEET C#
     string newStr = oldStr.Replace("old","new");
 
     //IndexOf
-    //Finds the first ocurrence of a string in a larger string
+    //Finds the first occurrence of a string in a larger string
     //Returns -1 if the string is not found
     String.IndexOf(val, start, num)
     val - string to search for
@@ -102,7 +102,7 @@ CHEATSHEET C#
     String.Split(Char[]);
 
     //ToCharArray
-    //Places selected characteres in a string in a char array
+    //Places selected characters in a string in a char array
     String str = "AaBbCcDd";
     //create array of 8 vowels
     var chars = str.ToCharArray();
@@ -135,7 +135,7 @@ CHEATSHEET C#
 
     6.1 TimeSpan Constructor
 
-    TimpeSpan(hour, minute, sec)
+    TimeSpan(hour, minute, sec)
 
     TimeSpan timeS = new TimeSpan(10, 14, 50);
     TimeSpan timeS_Hours = TimeSpan.FromDays(3640);
@@ -144,8 +144,8 @@ CHEATSHEET C#
 
     Format item syntax: {index[,alignment][:format string]}
     index - Specifies element in list of values to which format is applied
-    aligment - Indicates minimun width (in characters) to display value
-    format string - Contains the code which specififes the format of the displayed value
+    alignment - Indicates minimum width (in characters) to display value
+    format string - Contains the code which specifies the format of the displayed value
 
     7.1 Numeric
 
@@ -293,7 +293,7 @@ CHEATSHEET C#
     [access modifier] className (parameters) [:initializer]
 
     initializer -base calls constructor in base class.
-                 this calls constuctor within class.
+                 this calls constructor within class.
 
     public class nameClass : Initializer {
         public className(dataType param1 , dataType param2, ...) : base(param1, param2)
@@ -313,8 +313,8 @@ CHEATSHEET C#
     abstract – must be implemented by subclass
 
     Passing parameters:
-        1. By default, parametres are passed by value
-        2. Passing by reference: ref, in and out modifers
+        1. By default, parameters are passed by value
+        2. Passing by reference: ref, in and out modifiers
 
     To pass a parameter by reference with the intent of changing the value, use the ref, or out keyword. To pass by reference with the intent of avoiding copying but not changing the value, use the in modifier
 

languages/bash.sh

@@ -524,14 +524,14 @@ Cyan='\033[0;36m'   # Cyan
 White='\033[0;97m'  # White
 
 # Additional colors
-LGrey='\033[0;37m'  # Ligth Gray
+LGrey='\033[0;37m'  # Light Gray
 DGrey='\033[0;90m'  # Dark Gray
-LRed='\033[0;91m'   # Ligth Red
-LGreen='\033[0;92m' # Ligth Green
-LYellow='\033[0;93m'# Ligth Yellow
-LBlue='\033[0;94m'  # Ligth Blue
+LRed='\033[0;91m'   # Light Red
+LGreen='\033[0;92m' # Light Green
+LYellow='\033[0;93m'# Light Yellow
+LBlue='\033[0;94m'  # Light Blue
 LPurple='\033[0;95m'# Light Purple
-LCyan='\033[0;96m'  # Ligth Cyan
+LCyan='\033[0;96m'  # Light Cyan
 
 
 # Bold

languages/golang.md

@@ -397,8 +397,8 @@ d, t := doubleAndTriple(5)
 _, t := doubleAndTriple(3)
 // t = 9
 
-// Functions can defer commands. Defered commands are
-// runned in a stack order after the execution and
+// Functions can defer commands. Deferred commands are
+// ran in a stack order after the execution and
 // returning of a function
 var aux = 0
 
@@ -488,7 +488,7 @@ person3.Age // 0
 
 ## Maps
 
-Maps are data structures that holds values assigneds to a key.
+Maps are data structures that holds values assigned to a key.
 
 ```go
 // Declaring a map
@@ -508,7 +508,7 @@ newYork // "EUA"
 // Delete
 delete(cities, "NY")
 
-// Check if a key is setted
+// Check if a key is set
 value, ok := cities["NY"]
 ok // false
 value // ""

languages/java.md

@@ -308,7 +308,7 @@ for(dataType item : array) {
   //Declare a variable, object name
   String s;
 
-  //Invoke a contructor to create an object
+  //Invoke a constructor to create an object
   s = new String ("Hello World");
 
   //Invoke an instance method that operates on the object's value

languages/php.php

@@ -1,8 +1,8 @@
 <?php
 
 // Exit the file, string inside get's echo'ed
-die("This file is not ment to be ran. ¯\_(ツ)_/¯");
-exit("This file is not ment to be ran. ¯\_(ツ)_/¯");
+die("This file is not meant to be ran. ¯\_(ツ)_/¯");
+exit("This file is not meant to be ran. ¯\_(ツ)_/¯");
 
 /**
  * Printing
@@ -17,7 +17,7 @@ var_dump($arr); // Print anything, with type hints for any value and sizes
 $string = 'Awesome cheatsheets';
 
 str_contains($string, 'cheat'); // Find if the string contains the specified string (PHP >= 8.0)
-str_replace('Awesome', 'Bonjour', $string); // Replace all occurence
+str_replace('Awesome', 'Bonjour', $string); // Replace all occurrence
 strcmp($string, 'Awesome cheatsheets'); // Compare two strings
 strpos($string, 'a', 0); // Get position in the string
 str_split($string, 2); // Split the string
@@ -541,7 +541,7 @@ u   Pattern is treated as UTF-8
 \w  Any "word" character (a-z 0-9 _)
 \W  Any non "word" character
 \s  Whitespace (space, tab CRLF)
-\S  Any non whitepsace character
+\S  Any non whitespace character
 \d  Digits (0-9)
 \D  Any non digit character
 .   (Period) - Any character except newline

languages/python.md

@@ -71,7 +71,7 @@
 | import | import libraries/modules/packages | import |
 | from | import specific function/classes from modules/packages | import |
 | try | this block will be tried to get executed | exception handling |
-| except | is any exception/error has occured it'll be executed | exception handling |
+| except | is any exception/error has occurred it'll be executed | exception handling |
 | finally | It'll be executed no matter exception occurs or not | exception handling |
 | raise | throws any specific error/exception | exception handling |
 | assert | throws an AssertionError if condition is false | exception handling |

tools/cronjob.txt

@@ -0,0 +1,68 @@
+CRONTAB, is a time-based job scheduler in Unix like operating systems. 
+In laymen term, it is used to execute scripts on your machine at a predefined time or interval. 
+This can be any script, for instance downloading images from a particular website every hour or generating a pdf of your unread emails from the past day and the list goes on
+
+
+###################################
+BASICS
+###################################
+
+Each line of a crontab represents a job and it looks as follows:
+
+* * * * * command_name
+
+Each asterisk here has a special meaning :
+Asterisk 1 : Represents minutes from 0 to 59
+Asterisk 2 : Represents hour of the day from 0 to 23
+Asterisk 3: Represents day of the month from 1 to 31
+Asterisk 4: Represents a month from 1 to 12
+Asterisk 5: Represents the day of the week from 0 to 6 (Sunday to Saturday)
+Command : A command that executes a script
+
+Example : 0 10 * * * /bin/bash print_time.sh
+You can play with these settings from the following site : https://crontab.guru
+
+The above example will execute the script print_time.sh using the /bin/bash shell, everyday at 10:00 A.M. 
+Crontab uses a 24 hour clock
+Providing the full path to the script is necessary
+Providing a shell name or a specific interpreter is necessary too
+
+We can also use the following strings to define job.
+
+@reboot	Run once, at startup.
+@yearly	Run once a year.
+@annually	(same as @yearly).
+@monthly	Run once a month.
+@weekly	Run once a week.
+@daily	Run once a day.
+@midnight	(same as @daily).
+@hourly	Run once an hour.
+
+@reboot <command-to-execute> # run a job every time the system reboots
+
+###################################
+CREATING CRONTAB JOBS
+###################################
+
+crontab -e # this opens up the crontab file in your predefined editor
+
+# create a basic cronjob that runs everyday at 10:00 A.M.
+0 10 * * * /bin/bash ~/Documents/collect_log.sh 
+
+- this cronjob will get executed everyday at 10:00 AM
+- note the leading 0 is important
+- /bin/bash is the interpreter here, and this is required
+- ~/Documents/collect_log.sh is the absolute path to the script to be executed
+
+
+
+###################################
+VIEW CRONJOBS FOR THE CURRENT USER
+###################################
+crontab -l 
+
+
+##########################################
+REMOVE ALL CRONJOBS FOR THE CURRENT USER
+##########################################
+crontab -r

tools/vim.txt

@@ -20,13 +20,15 @@ e                   jump to end of words (punctuation considered words)
 E                   jump to end of words (no punctuation)
 b                   jump backward by words (punctuation considered words)
 B                   jump backward by words (no punctuation)
-ge                  jump backward to end of words
+ge                  jump backward to end of a word
+gE                  jump backwards to the end of a word (words can contain punctuation)
 0                   (zero) start of line
 ^                   first non-blank character of line
-$                   end of line
--                   move line upwards, on the first non blank character
-+                   move line downwards, on the first non blank character
-<enter>             move line downwards, on the first non blank character
+$                   jump to the end of the line
+g_                  jump to the last non-blank character of the line
+-                   move line upwards, on the first non-blank character
++                   move line downwards, on the first non-blank character
+<enter>             move line downwards, on the first non-blank character
 gg                  go to first line
 G                   go to last line
 ngg                 go to line n
@@ -38,10 +40,6 @@ nG                  go To line n
 }                   move the cursor a paragraph forwards
 ]]                  move the cursor a section forwards or to the next {
 [[                  move the cursor a section backwards or the previous {
-CTRL-f              move the cursor forward by a screen of text
-CTRL-b              move the cursor backward by a screen of text
-CTRL-u              move the cursor up by half a screen
-CTRL-d              move the cursor down by half a screen
 H                   move the cursor to the top of the screen.
 M                   move the cursor to the middle of the screen.
 L                   move the cursor to the bottom of the screen.
@@ -49,6 +47,16 @@ fx                  search line forward for 'x'
 Fx                  search line backward for 'x'
 tx                  search line forward before 'x'
 Tx                  search line backward before 'x'
+CTRL-y              moves screen up one line
+CTRL-e              moves screen down one line
+CTRL-u              moves cursor & screen up ½ page
+CTRL-d              moves cursor & screen down ½ page
+CTRL-b              moves screen up one page, cursor to last line
+CTRL-f              moves screen down one page, cursor to first line
+zz                  shift current line to middle of screen
+z.                  same as zz but also jumps to the first non-black character
+zt                  shift current line to top of screen
+zb                  shift current line to bottom of screen
 
 
 ##############################################################################
@@ -60,8 +68,15 @@ Tx                  search line backward before 'x'
 ma                  make a bookmark named a at the current cursor position
 `a                  go to position of bookmark a
 'a                  go to the line with bookmark a
+`0                  go to the position where Vim was previously exited
+`"                  go to the position when last editing this file
 `.                  go to the line that you last edited
+``                  go to the position before the last jump
+g,                  go to newer position in change list
+g;                  go to older position in change list
 
+# Tip: To jump to a mark you can either use a backtick (`) or an apostrophe (').
+# Using an apostrophe jumps to the beginning (first non-blank) of the line holding the mark.
 
 ##############################################################################
 # INSERT MODE
@@ -70,10 +85,13 @@ ma                  make a bookmark named a at the current cursor position
 
 i                   start insert mode at cursor
 I                   insert at the beginning of the line
+gi                  return to insert mode where you inserted text the last time
+gI                  like "I", but always start in column 1
 a                   append after the cursor
 A                   append at the end of the line
 o                   open (append) blank line below current line
 O                   open blank line above current line
+CTRL-o              Temporarily enter normal mode to issue one normal-mode command(while in insert mode)
 Esc                 exit insert mode
 
 
@@ -84,10 +102,25 @@ Esc                 exit insert mode
 
 r                   replace a single character (does not use insert mode)
 R                   enter Insert mode, replacing characters rather than inserting
-J                   join line below to the current one
+J                   join line below to the current one with one space in between
+gJ                  join line below to the current one without space in between
 cc                  change (replace) an entire line
-cw                  change (replace) to the end of word
-C                   change (replace) to the end of line
+cw                  change (replace) to the end of word (same as ce)
+2cw                 change (replace) repeat cw twice
+ciw                 change (replace) word under the cursor
+caw                 change (replace) word under the cursor and the space after or before it
+ci"                 change (replace) word inside ""
+cit                 change (replace) html tag content
+cat                 change (replace) html tag
+cis                 change (replace) sentence under the cursor
+cas                 change (replace) sentence under the cursor and the space after or before it
+cib                 change (replace) inside a block with ()
+cab                 change (replace) a block with ()
+ciB                 change (replace) inside a block with {}
+caB                 change (replace) a block with {}
+C                   change (replace) to the end of line(same as c$)
+cG                  change (replace) to the end of the file
+cgg                 change (replace) from first line to current line
 ct'                 change (replace) until the ' character (can change ' for any character)
 s                   delete character at cursor and substitute text
 S                   delete line at cursor and substitute text (same as cc)
@@ -102,6 +135,7 @@ guiw                make current word lowercase
 gU$                 make uppercase until end of line
 gu$                 make lowercase until end of line
 >>                  indent line one column to right
+>i{                 indent everything in the {}
 <<                  indent line one column to left
 ==                  auto-indent current line
 ddp                 swap current line with next
@@ -110,6 +144,7 @@ ddkP                swap current line with previous
 :r [name]           insert the file [name] below the cursor.
 :r !{cmd}           execute {cmd} and insert its standard output below the cursor.
 
+# Tip: Instead of b or B one can also use ( or { respectively.
 
 ##############################################################################
 # DELETING TEXT
@@ -118,10 +153,15 @@ ddkP                swap current line with previous
 
 x                   delete current character
 X                   delete previous character
-dw                  delete the current word
+dw                  delete (cut) to the end of word (same as de)
+diw                 delete (cut) word under the cursor
+daw                 delete (cut) word under the cursor and the space after or before it
+dap                 delete (cut) a paragraph
 dd                  delete (cut) a line
-dt'                 delete until the next ' character on the line (replace ' by any character)
-D                   delete from cursor to end of line
+dt'                 delete (cut) until the next ' character on the line (replace ' by any character)
+dG                  delete (cut) to the end of the file
+dgg                 delete (cut) from first line to current line
+D                   delete (cut) from cursor to end of line (same as d$)
 :[range]d           delete [range] lines
 
 
@@ -136,6 +176,10 @@ yy                  yank (copy) a line
 y$                  yank to end of line
 p                   put (paste) the clipboard after cursor/current line
 P                   put (paste) before cursor/current line
+gp                  put (paste) the clipboard after cursor and leave cursor after the new text
+gP                  put (paste) before cursor and leave cursor after the new text
+"+y                 yank into the system clipboard register
+"+p                 paste from the system clipboard register
 :set paste          avoid unexpected effects in pasting
 :registers          display the contents of all registers
 "xyw                yank word into register x
@@ -147,6 +191,12 @@ P                   put (paste) before cursor/current line
 "xgP                just like "P", but leave the cursor just after the new text
 :[line]put x        put the text from register x after [line]
 
+# Tip: if you are using vim extension on vs code, you can enable
+"vim.useSystemClipboard": true
+in setting.json, this will allow to Use system clipboard for unnamed register.
+
+
+
 
 ##############################################################################
 # MACROS
@@ -157,6 +207,7 @@ qa                  start recording macro 'a'
 q                   end recording macro
 @a                  replay macro 'a'
 @:                  replay last command
+@@                  repeat macro
 
 
 ##############################################################################
@@ -172,9 +223,11 @@ CTRL-v              start visual block mode
 O                   move to other corner of block
 aw                  mark a word
 ab                  a () block (with braces)
-ab                  a {} block (with brackets)
+aB                  a {} block (with brackets)
+at                  a block with <> tags
 ib                  inner () block
-ib                  inner {} block
+iB                  inner {} block
+it                  inner <> block
 Esc                 exit visual mode
 
 VISUAL MODE COMMANDS
@@ -194,6 +247,7 @@ v%                  selects matching parenthesis
 vi{                 selects matching curly brace
 vi"                 selects text between double quotes
 vi'                 selects text between single quotes
+gv                  reselect the last selected area
 
 ##############################################################################
 # SPELLING
@@ -283,7 +337,6 @@ CTRL-w <            increase window width
 CTRL-w >            decrease window width
 CTRL-w =            equal window
 CTRL-w o            close other windows
-zz                  Centers the window to the current line
 
 
 ##############################################################################
@@ -306,12 +359,14 @@ clast               display the last error
 
 
 %                   show matching brace, bracket, or parenthese
-gf                  edit the file whose name is under or after the cursor
+gf                  edit the file whose name is under the cursor
+gF                  edit the file whose name is under the cursor and jump to the line number
 gd                  when the cursor is on a local variable or function, jump to its declaration
 ''                  return to the line where the cursor was before the latest jump
-gi                  return to insert mode where you inserted text the last time
 CTRL-o              move to previous position you were at
 CTRL-i              move to more recent position you were at
+:set nu             display numbers (short for :set number)
+:set nonu           hide numbers (short for :set nonumber)
 
 
 ##############################################################################