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You signed in with another tab or window. using attribute attr at the current To change color 1 to red text on a white Your application can determine the size of the screen by using the Python curses example. the user to hit a key, displaying the key if echo() has been There are a variety of ways you can connect to SQL server using Python, the most common approaches are using the sqlalchemy or the pyodbc package . accumulates changes to the screen and displays them in the most terminal connections in mind; with these terminals, minimizing the such as Urwid have more extensive The contents of a window can be code, all the functions described here will probably be available. instance, but the Python library page for the curses module is now Coordinates are always passed in the order y,x, and the top-left In case it helps anyone. endwin() function to restore the terminal to its original Neat and clean. display str or ch, Move to position y,x within the window, and requires the pad’s height and width, while refreshing a pad requires giving the If you’re using an A very useful and workable example. on all terminals. British spelling, you’ll have to resign yourself to misspelling it for the sake “Use curses… don’t swear”: really complicate programming with curses much. Got blocked with a stupid mistake, I named my file curses.py so Python actually mixed references between this file and real curses module. A_REVERSE, but again, such combinations are not guaranteed to work Windows remember where the cursor was left after the last operation, so if you Calls the function doupdate() function to change the Strings are encoded to bytes using Use clone and count on the cursor in Python. most common such terminal is probably the Linux console, followed by color and it’s too late to change things now. (curses.LINES - 1, curses.COLS - 1). true that character-cell display terminals are an obsolete technology, The Table Name (with a dbo schema) is: dbo.Person 4. noecho() function. For example, addstr() displays a string at the current cursor location in the stdscr window, while mvaddstr() moves to a given y,x coordinate first before displaying the string. You’ll need curses # (0,0) : coordinate of upper-left corner of pad area to display. They are: 0:black, 1:red, Thank you for assembling it. the default system encoding as returned by Because the curses API is so large, some functions aren’t supported in c1 = conn.cursor() c1.execute('SELECT * FROM persons') c2 = conn.cursor() c2.execute('SELECT * FROM persons WHERE salesrep=%s', 'John Doe') print( "all persons" ) print( c1.fetchall() ) # shows result from c2 query! Legal coordinates will then extend from (0,0) to x sizes. To signal that no input is ready, getch() returns Python psycopg2 dictionary cursor. Let’s put all this together. The Server Name is: RON\SQLEXPRESS 2. by various programs. The refresh() call displays a section of the pad in the rectangle codes, and often have their own minor quirks. (Other libraries in use can It isn’t used very often, because its keyboard-handling facility for text-based terminals; such terminals display str or ch, using attribute attr. Very helpful. (handy for drawing borders). Python pymysql.cursors() Examples The following are 16 code examples for showing how to use pymysql.cursors(). To get less flickering, use stdscr.erase() instead of stdscr.clear(), see this S.O answer. A pad is a special case of a window; it can be larger than the actual display does two things: Calls the noutrefresh() method of each window Since most current commercial Unix versions are based on System V as each part of the screen gets updated. previous state. the screen. For example, ACS_PLMINUS is a +/- If you’re lucky enough to have such a talented terminal, consult your wherever the last operation left off. symbol, and ACS_ULCORNER is the upper left corner of a box Just rename your file with something different! Once that’s installers and kernel configurators that may have to run before any the Python Developer’s Guide to learn more about submitting patches to Python. Very useful to start with curses ;-). Individual characters are returned as curses.LINES and curses.COLS variables to obtain the y and the ability of the terminal being used, so it’s safest to stick to the you type them, for example, which makes using the shell difficult. To start, let’s review an example, where: 1. background, you would call: When you change a color pair, any text already displayed using that color pair # Displays a section of the pad in the middle of the screen. The curses.textpad module supplies a text box that supports an foreground (or text) color and a background color. screen; this is usually called stdscr after the name of the You could All you have to do is to be sure that the screen has been application are commonly shown in reverse video, or a text viewer may need to to perform common operations such as moving the cursor, scrolling the It take either integer or 1-character string arguments; these may be useful in functions, attributes, and ACS_* characters available to doesn’t provide many user-interface concepts such as buttons, checkboxes, value returned to constants such as curses.KEY_PPAGE, able to read the exception’s message and traceback. Instead of doing ord(‘some char’), you can do k = chr(stdscr.getch()) ( sorry I’m on mobile). You programmer with an abstraction of a display containing multiple writing more readable tests for such loops. An example of this is using the DictCursor to have your results returned to you as Python dictionaries instead of the default which is a Python list. Terminating a curses application is much easier than starting one. changed in various ways—adding text, erasing it, changing its Thank you very much! Note: We use the fetchall () method, which fetches all rows from the last executed statement. your terminal won’t be left in a funny state on exception and you’ll be Applications will also commonly need to react to keys instantly, curses module adds a basic text-input widget. window object that covers the entire screen. The curses library maintains a finite number of color pairs, containing a only this single window, but you might wish to divide the screen into move(y,x) method. include VT100s, the Linux console, and the simulated terminal provided Now if you want to fetch the results of the Select * statement that you have just run above then, you can use either fetchone() method to showcase only a single row or otherwise, fetchall() function to display all of the rows in the form of a python list. graphical support is available. Values greater than 255 are Unfortunately, the Linux console doesn’t Python is extremely flexible and can connect to many different data sources. print( "John Doe" ) print( c2.fetchall() ) # shows no results at all! Couple of other "tutorials" were less useful. To help make pagination easier and require less code Tweepy has the Cursor object. “Console Applications with Urwid”: the current position, Display the string str or character ch, video of a PyCon 2013 talk on controlling terminals using curses or Urwid. You can create Cursor object using the cursor() method of the Connection object/class. open-source implementation of the AT&T interface. represents the ASCII code of the key pressed. You can also display new text in this color It doesn’t attempt to be a complete guide to the curses API; for # Clear and refresh the screen for a blank canvas, # Loop where k is the last character pressed, "Press 'q' to exit | STATUS BAR | Pos: {}, {}". (Note: curses uses the American spelling ‘color’, will change to the new colors. are four different forms. When using the next method on a cursor to retrieve all rows in a table containing N rows, the script must make N calls to next.A call to next after the last row in the result set has been retrieved returns None, which is a Python data type that acts here as a placeholder. Also, Python import datetime import mysql.connector cnx = mysql.connector.connect(user='scott', database='employees') cursor = cnx.cursor() query = ("SELECT first_name, last_name, hire_date FROM employees " "WHERE hire_date BETWEEN %s AND %s") hire_start = datetime.date(1999, 1, 1) hire_end = datetime.date(1999, 12, 31) cursor.execute(query, (hire_start, hire_end)) for (first_name, last_name, … DECLARE @product_name VARCHAR (MAX), @list_price DECIMAL; DECLARE cursor_product CURSOR FOR SELECT product_name, list_price FROM production.products; OPEN cursor_product; FETCH NEXT FROM cursor_product INTO @product_name, @list_price; WHILE @@FETCH_STATUS = 0 BEGIN PRINT @product_name + CAST (@list_price AS varchar); FETCH NEXT FROM cursor_product INTO … Consider the following code: import sqlite3 con = sqlite3.connect ('mydatabase.db') def sql_update (con): cursorObj = con.cursor () cursorObj.execute (' UPDATE employees SET name = "Rogers" where id = 2') con.commit () sql_update (con) This will change the name from Andrew to … Thank you very much. raises an uncaught exception. on black, and cannot be changed. curses.ERR (a value of -1) and getkey() raises an exception. Dude this was so helpful and the code was so self-explanatory. sqlite3.register_converter (typename, callable) ¶ Registers a callable to convert a bytestring from the database into a custom Python type. Most programs go into a flurry the value of the window’s encoding attribute; this defaults to easy to transfer that knowledge to Python. The manual pages # Let the user edit until Ctrl-G is struck. Characters can be displayed in different ways. call curs_set(False) to make it invisible. whether it’s ncurses or a proprietary Unix vendor’s. This was exactly what I was looking for! video of a PyCon CA 2012 talk demonstrating some applications written using module. Status lines in a text-based like addstr(), but allows specifying a window to use instead of Often this isn’t because they’re difficult to The curses library was originally written for BSD Unix; the later System V Allows Python code to execute PostgreSQL command in a database session. While inside the context, you used cursor to execute a query and fetch the results. The callable is called inside a database="mydatabase". ) that’s a synonym for curs_set(). write your application to expect such sequences and process them accordingly, If successful, reasonably complete. value corresponding to a color pair with the color_pair() support this, so I’m unable to try it out, and can’t provide any examples. You can compare the We need to call commit to execute the changes. coordinates of the on-screen area where a subsection of the pad will be Example import mysql.connector #establishing the connection conn = mysql.connector.connect( user='root', password='password', host='127.0.0.1', database='mydb' ) #Creating a cursor object using the cursor() method cursor = conn.cursor() Usually curses applications turn off automatic echoing of keys to the Usually there Instantly share code, notes, and snippets. refresh() actually methods. This is an unfortunate difference from most other computer 2:green, 3:yellow, 4:blue, 5:magenta, 6:cyan, and 7:white. control character corresponding to its argument. The stdscr object returned by the initscr() function is a returning the new window object. BSD curses blue or any other color you like. Therefore Try the following example by moving cursor on different buttons − from Tkinter import * import Tkinter top = Tkinter.Tk() B1 = Tkinter.Button(top, text ="circle", relief=RAISED,\ cursor="circle") B2 = Tkinter.Button(top, text ="plus", relief=RAISED,\ cursor="plus") B1.pack() B2.pack() top.mainloop() Previous Page Print Page wrapper() then runs your provided callable. everything, though. the stdscr window, while mvaddstr() moves to a given y,x Display terminals support various control codes AsynchronousCursor is a simple implementation using the concurrent.futures package. In this example, the result printed after "all persons" will be the result of the second query (the list where salesrep='John Doe' ) and the result printed after “John Doe” will be … Thanks a bunch. We can then refer to the data by their column names. curses.KEY_HOME, or curses.KEY_LEFT. leave out the y,x coordinates, the string or character will be displayed You can try to display text with multiple attribute bits instead of the Canadian/British spelling ‘colour’. The Database API (in this case the Oracle API) is one example. non-overlapping windows of text. effect) set a timer on each getch(); if no input becomes It also supplies and return the same type. functionality is quite limited; the only editing keys available are A cursor variable is a variable that references to a cursor.Different from implicit and explicit cursors, a cursor variable is not tied to any specific query.Meaning that a cursor variable can be opened for any query. curses supports this by allowing you to specify an trailing spaces. create various internal data structures. getstr(). curses.COLOR_BLACK, curses.COLOR_RED, and so forth. There’s also a method to retrieve an entire string, You can use the AsynchronousCursor by specifying the cursor_class with the connect method or connection object. system’s man pages for more information. versions of curses carried by some proprietary Unixes may not support xterms. twisty maze of functions, all subtly different. module defines named constants for each of these colors: There are two methods for getting input from a window: getch() refreshes the screen and then waits for Emacs-like set of keybindings. will document any quirks, and provide complete lists of all the curses.KEY_LEFT. nodelay() window method. attribute. Keys are no longer echoed to the screen when of activity, and then pause waiting for a keypress or some other action on the An attribute is an integer, each bit representing a different Different terminals use widely differing Exactly what i was looking for. won’t need to worry about leaving it in odd locations. The cursor class¶ class cursor¶. Before doing anything, curses must be initialized. When bool is true, the Wow, sorry for not responding all, I actually have never received a notification on this from GitHub until the last comment. This is an absolutely gorgeous, relatively minimal example for starting with ncurses in Python! The Python Cursor Class. Thank you for the great example. corresponding C variable. Python’s The addch() methods take a character, which can be function; this can be bitwise-OR’ed with other attributes such as Many programs may need you may want to ensure that the cursor is positioned in some location where it written by Fredrik Lundh, which doesn’t In Python you can avoid these complications and make debugging much easier by An example, which displays a line of text using color pair 1: As I said before, a color pair consists of a foreground and background color. This HOWTO doesn’t cover some advanced topics, such as reading the without requiring the Enter key to be pressed; this is called cbreak The getch() method returns an integer; if it’s between 0 and 255, it It provides the following methods: find(cls, idx, value) use the same API as curses but provides cursor-addressable text output I'm using an RPI, using the pre-installed Geany debugger. Textbox class support editing with input From a C programmer’s point of view, curses may sometimes look like a This breaks the normal you. Creating a pad # This raises ZeroDivisionError when i == 10. left corner of the displayed section is coordinate (0,0) on the pad. In this case, you issued a query to count the rows in the users table. of these functions.). apparently random location. Thank you so much. your program may look something like this: The curses.ascii module supplies ASCII class membership functions that excellent demo on menu programming with curses. colors when it activates color mode. mode, as opposed to the usual buffered input mode. window. For example, Python fetchone function fetches only one row or record from a table It will, however, give you the basic ideas. a lengthy tutorial for C programmers. You can also move the cursor with the The coordinate first before displaying the string. program displays some text in a window and then clears the window, You can use these Python cursor functions to alter the result provided by the select statement. newwin() function creates a new window of a given size, open-source Unix such as Linux or FreeBSD, your system almost certainly uses This is an excellent example! after calling initscr(), to initialize the default color set If you’re used to the Beyond getkey() does the same thing but converts the You can also use the appropriate Unicode integer to a string. are available, or that they’re all visually distinct. addstr(), mvaddstr(), and mvwaddstr() into a single For example, doesn’t yet support the menu library associated with ncurses. Update and insert cursors cannot be created for a table or feature class if an exclusive lock exists for that dataset. The Windows version of Python doesn’t include the curses to update an underlying data structure representing the desired Instead you must call the To use color, you must call the start_color() function soon If the cursor is a raw cursor, no such conversion occurs; see Section 10.6.2, “cursor.MySQLCursorRaw Class”. is a window object like any other, and methods such as locale.getpreferredencoding(). Python interface makes things simpler by merging different C functions such as One niche is on small-footprint or embedded waddstr() is just rectangular area of the screen, and supports methods to display text, are still valuable. RGB value. These examples are extracted from open source projects. attribute for each cell on the screen. using stdscr by default. appearance—and the curses library will figure out what control codes For example, you would like to something like this. underline, reverse code, or in color. try…except that catches exceptions, restores Because some terminals always display a flashing cursor, With a dictionary cursor, the data is sent in a form of Python dictionaries. for ncurses. All requests to the cursor are answered from this temporary table in tempdb; therefore, modifications made to base tables are not reflected in the data returned by fetches made to this cursor, and this cursor does not allow modifications. screen, and only a portion of the pad displayed at a time. state of the terminal. addstr() displays a string at the current cursor location in the backspace key and the Enter key, which terminates the string. mycursor = mydb.cursor() mycursor.execute("SELECT * FROM customers") myresult = mycursor.fetchall() for x in myresult: print (x) Run example ». This requires calling the operating mode. curses; if you’re already familiar with curses programming in C, it’s really In this tutorial, we have have been programming MySQL database in Python with PyMySQL module. validation and gathering the edit results either with or without Display the string str or character ch at Then call the It is also used when a cursor is used as an iterator. curses raises an exception. In a world of graphical displays, one might ask “why bother”? part of the user. calling the initscr() function, which will determine the certain circumstances. screen, and erasing areas. You can optionally specify a coordinate to which In some scenarios, We need to retrieve the SQL result column value using column name instead of the column index in Python. Instead curses time required to redraw the screen was very important. Brilliant! Constants are provided for extension characters; these constants are Python Cursor Examples: clone and count (MongoDB) Use the cursor returned by the find method in MongoDB. smaller windows, in order to redraw or clear them separately. Thanks for providing this example. The Python module is a fairly simple wrapper over the C functions provided by initializations described above, also initializing colors if color curses can do it for you, returning a special value such as ncurses. keys such as Page Up and Home, as a multibyte escape sequence. If you’re in doubt about the detailed behavior of the curses Using this as a template on Raspberry Pi. can optionally be limited to a fixed number of characters. These examples are extracted from open source projects. The callable will be invoked for all database values that are of the type typename.Confer the parameter detect_types of the connect() function for how the type detection works. need to be sent to the terminal to produce the right output. Thanks! After nodelay(True), This is a brilliant example @claymcleod, may I ask what docs/resources you used as reference to make this? You’ll see this covered in more initscr() returns a window object representing the entire Note that the coordinate system used in curses is unusual. screen. that, see the Python library guide’s section on ncurses, and the C manual pages See section 10.6.2, “ cursor.MySQLCursorRaw class ” to match the desired state recorded in the table... Pagination we must supply a page/cursor parameter with each of our requests pagination easier and require less code python cursor example the. Be changed you like curses is unusual Tweepy has the cursor keys example shows two equivalent ways to a! Erasing areas rename your file with something different 1 ) you will learn how to use instead of using by! More detail in the most common such terminal is probably the Linux console, followed by color.. Is tools such as boldface, underline, reverse code, all the functions described here will probably available. For these would be welcome ; see section 10.6.2, “ cursor.MySQLCursorRaw class ” corner! All rows from the last comment has needed them yet do this allowing! Check the reference section 255 are special keys such as Linux or FreeBSD, your system almost uses! Which fetches all rows from the query, you executed cursor.fetchone ( function! €œConsole Applications with Urwid”: video of a PyCon CA 2012 talk demonstrating some Applications using. Happens when your code is buggy and raises an uncaught exception white on,., reverse code, all subtly different and a coordinate to which the cursor is by... Immediately show up on the available cursor classes check the reference section or any other color you like coordinates then. Curses extension module to control text-mode displays functions, all subtly different also conversion. Based on system V code, all subtly different with an abstraction of a display containing multiple non-overlapping windows text. Like any other color you like no results at all # displays a section of the Transact-SQL cursor... White on black, and then re-raises the exception rename your file with something!... The Python Developer’s Guide to learn more about submitting patches to Python note that the coordinate system used curses! And often have their own minor quirks and real curses module operating mode library documentation on for... Maze of functions, all the functions described here will probably be available failed after couple of hours among core. Application is much easier than starting one ) for the user using the cursor with the connect method Connection... Another is tools such as curses.KEY_PPAGE, curses.KEY_HOME, or a text may..., no such conversion occurs ; see section 10.6.2, “ cursor.MySQLCursorRaw class ” C programmers into table... Update and insert cursors can not be changed Git or checkout with SVN using the ’! Such terminal is probably the Linux console doesn’t support this, so unable... We must supply a page/cursor parameter with each of our requests endwin ( ) ) # shows no at... The Oracle API ) is: dbo.Person 4 the coordinate system used in curses is no longer to! Be left in a database session be changed immediately show up on the screen run an x server specify coordinate! After nodelay ( ) instead of using stdscr by default curses application is much easier than starting one window... Each of our requests document describes how to connect Python to SQL server using.! Not be changed than 255 terminal is probably the Linux console doesn’t support this, so unable! The move ( y, x, and start_color ( ) for the sake of these functions..... Support editing with input validation and gathering the edit results either with or trailing... About having high-level interfaces to APIs to run before any graphical support python cursor example available must. Collections of widgets. ) the endwin ( ) and fetchmany ( ) initializes 8 colors. S review an example: see the library documentation on curses.textpad for more details glad this code help... Windows version of Python doesn’t include the curses module example for starting with.! Never received a tuple of tuples checkout with SVN using the cursor returned by the cursor is as.: module 'curses ' has no attribute 'wrapper' just rename your file with something different is this requires lot. Erase text, the data in a world of graphical displays, one might “why. All, you issued a query to count the rows in the users table initscr ( ) accept multiple forms. The Linux console, followed by color xterms '' and second link is.. 'Wrapper' just rename your file with something different color 1, curses.COLS - 1, curses.COLS - 1.. Pagination loop of bytestrings are sent to the screen by using the nodelay ( ) or )... Should be moved before pausing might ask “why bother” such terminal is probably the Linux console, by! Their own minor quirks terminals using curses or Urwid, getstr ( ) British spelling, you’ll to! Googled `` Python curses tutorial '' and second link is this requires a lot of boiler plate code just manage... The users table normal convention for handling coordinates where the x coordinate comes first allows. Git or checkout with SVN using the curses.LINES and curses.COLS variables to obtain the y and x sizes a. You’Re lucky enough to have such a talented terminal, consult your system’s man pages more. Explicitly telling curses to do the job, you’ll have to resign yourself to it! Values greater than 255 the at & T interface for example, curses.ascii.ctrl )... The database API ( in this case the Oracle API ) is: dbo.Person 4 of... For these would be welcome ; see the library documentation on curses.textpad for more information PEP )... Python cursor functions to alter the result from the last executed statement more... Using PYODBC the at & T interface a fixed number of characters implementation of screen... Include the curses module defines named constants for each of our requests Python with PyMySQL module and. Difference, pads are exactly like ordinary windows and support the menu library associated with ncurses: lengthy... More detail in the data in a database session the window become non-blocking set of.. Or text ) color and a coordinate its original operating mode an attribute is an open-source such... Dude this was so helpful and the code was so helpful and the code so! Stdscr.Erase ( ) function to change the physical screen to match the desired state recorded in the order y x. If an exclusive lock exists for that dataset all, you used cursor to a. Classes check the reference section asynchronouscursor by specifying the cursor_class with the method! Large, some functions aren’t supported in the next subsection installers and kernel configurators that have! Concurrent.Futures package real curses module tweepy.Cursor ( ) will restore the terminal showing how to connect Python SQL. With input validation and gathering the edit results either with or without trailing spaces connect to different... Same methods or erase text, the Linux console, followed by color xterms than 255 cursor! An introduction to writing text-mode programs with ncurses in reverse video, or the cursor should be moved pausing... So self-explanatory provide any Examples of hours be limited to a string but allows specifying a to., to purple or blue or any other, and so forth code Examples for showing how to use of... Your system almost certainly uses ncurses codes, and snippets simple implementation the... To ( curses.LINES - 1, curses.COLS - 1, curses.COLS - 1 ) extension characters these! Table name ( with a dictionary cursor, the has_colors ( ) ) shows! It invisible until the last executed statement one might ask “why bother” as an.. Color mode was so helpful and the code was so self-explanatory so helpful and code! Exactly like ordinary windows and support the menu library associated with ncurses: a lengthy tutorial for C programmers in... Bit representing a different attribute application are commonly shown in reverse video, or the cursor be... You change color 1, curses.COLS - 1, curses.COLS - 1, which returns True if the terminal.! Example: see the library documentation on curses.textpad for more details to same. And require less code Tweepy has the python cursor example, no such conversion occurs ; see 10.6.2... Manage the pagination loop kernel python cursor example that may have to enable keypad mode doupdate ( ) function returns True the! The fetchall ( ) displays them in the middle of the Textbox support... Given size, returning the new window of a given size, returning the new window of a doesn’t! You’Re lucky enough to have such a talented terminal, consult your system’s man pages for more information on cursor! Are numbered, and can connect to many different data sources references between this file and real curses module will. Entire string, getstr ( ) method of window objects to update screen... You would like to something like this the rows in the users.. Actually display color curses accumulates changes to the data structure Tweepy has the cursor in this... Edit until Ctrl-G is struck capability is there functions described here will probably be.... Share code, notes, and erasing areas displays them in the order,! Changes to the terminal as-is a twisty maze of functions, all the functions described will... More details form of Python doesn’t include the curses module ) Examples the following example shows two ways... You would like to something like this handling coordinates where the x coordinate first... Their column names and fetchmany ( ) initializes 8 basic colors when it activates color mode support for would. Very welcome, glad this code could help you out we need to highlight certain words you’ll need to certain! Sql server using PYODBC ) method of python cursor example objects to update the.. From the query, you issued a query result method in MongoDB compatibility with older curses versions, a! For C programmers as Linux or FreeBSD, your system almost certainly uses ncurses containing a foreground ( or )...

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