To edit commandline Anki flashcards in MySQL

The apkg files contain an embedded sqlite database file. For instance the deck Capital Cities of South America is downloaded as Capital_Cities_of_South_America.apkg which actually is a zip file. Unzipping this will extract several files

$ unzip ../Capital_Cities_of_South_America.apkg
Archive:  ../Capital_Cities_of_South_America.apkg
  inflating: collection.anki2        
 extracting: 0                       
 extracting: 1                       
 extracting: 2                       
 extracting: 3                       
 extracting: 4                       
 extracting: 5                       
 extracting: 6                       
 extracting: 7                       
 extracting: 8                       
 extracting: 9                       
 extracting: 10                      
 extracting: 11                      
  inflating: media                   
$

but the interesting one is collection.anki2 which is a sqlite file.

$ sqlite3 collection.anki2   
SQLite version 3.13.0 2016-05-18 10:57:30
Enter ".help" for usage hints.
sqlite> .tables
cards   col     graves  notes   revlog
sqlite> .dump notes
PRAGMA foreign_keys=OFF;
BEGIN TRANSACTION;
CREATE TABLE notes (
    id              integer primary key,   /* 0 */
    guid            text not null,         /* 1 */
    mid             integer not null,      /* 2 */
    mod             integer not null,      /* 3 */
    usn             integer not null,      /* 4 */
    tags            text not null,         /* 5 */
    flds            text not null,         /* 6 */
    sfld            integer not null,      /* 7 */
    csum            integer not null,      /* 8 */
    flags           integer not null,      /* 9 */
    data            text not null          /* 10 */
);
INSERT INTO "notes" VALUES(1475868715241,'P1Dh$4r;;P',1475850444584,1476205558,13,' South_America capitals ','Capital of French Guiana?Cayenne<div><br /></div><div><img src="053_Hood_135.jpg" /></div>','Capital of French Guiana?',511387741,0,'');
INSERT INTO "notes" VALUES(1476020723949,'D3h>i:~1(}',1475850444584,1476205484,13,' South_America capitals ','Capital of Brazil?Brasilia<div><br /></div><div><img src="brasilia-006.jpg" /></div>','Capital of Brazil?',139249191,0,'');
INSERT INTO "notes" VALUES(1476020740304,'I=w5}{qq&z',1475850444584,1476021426,4,' South_America capitals ','Capital of Argentina?Buenos Aires','Capital of Argentina?',4279953785,0,'');
INSERT INTO "notes" VALUES(1476020761836,'PpW<QQ2n;<',1475850444584,1476205269,13,' South_America capitals ','Capital of Chile?Santiago<div><br /></div><div><img src="santiago.jpg" /><br /><div><br /></div><div><br /></div></div>','Capital of Chile?',857145718,0,'');
INSERT INTO "notes" VALUES(1476020893034,'AQILm-om{w',1475850444584,1476205286,13,' South_America capitals ','Capital of Suriname?Paramaribo<div><br /></div><div><img src="paste-68513318306560.jpg" /><br /><div><br /></div><div><br /></div></div>','Capital of Suriname?',3475624840,0,'');
INSERT INTO "notes" VALUES(1476021133011,'ssX|ur}vz;',1475850444584,1476205460,13,' South_America capitals ','Capital of Guyana?Georgetown<div><br /></div><div><img src="georgetown-guyana.jpg" /></div>','Capital of Guyana?',1383243232,0,'');
INSERT INTO "notes" VALUES(1476021159549,'d_}(&UOcN0',1475850444584,1476205474,13,' South_America capitals ','Capital of Venezuela?Caracas<div><br /></div><div><img src="CaracasAvila.jpg" /></div>','Capital of Venezuela?',3460219780,0,'');
INSERT INTO "notes" VALUES(1476021305082,'hF6^dUFOU_',1475850444584,1476205202,13,' South_America capitals ','Capital of Colombia?Bagota<div><br /></div><div><!--anki--><img src="asuncion-paraguay.jpg" /></div>','Capital of Colombia?',3745298320,0,'');
INSERT INTO "notes" VALUES(1476021329578,'BF<CKCw&@X',1475850444584,1476021353,4,' South_America capitals ','Capital of Ecuador?Quito','Capital of Ecuador?',93805795,0,'');
INSERT INTO "notes" VALUES(1476021353212,'s-x)P3;UJ+',1475850444584,1476205337,13,' South_America capitals ','Capital of Peru?Lima<div><br /></div><div><img src="lima-miraflores-rw.jpg" /></div>','Capital of Peru?',1899195448,0,'');
INSERT INTO "notes" VALUES(1476021369814,'p~,SBD&um#',1475850444584,1476205352,13,' South_America capitals ','Capital of Bolivia?La Paz<div><br /></div><div><img src="La_Paz_Skyline.jpg" /></div>','Capital of Bolivia?',2475357406,0,'');
INSERT INTO "notes" VALUES(1476021495601,'h(+l3fJs48',1475850444584,1476205311,13,' South_America capitals ','Capital of Uruguay?Montevideo<div><br /></div><div><img src="montevideo-uruguay.jpg" /></div><div><br /></div><div>[sound:rec1476205311.mp3]</div>','Capital of Uruguay?',3423412928,0,'');
INSERT INTO "notes" VALUES(1476021520017,'g[QWvAO[:]',1475850444584,1476205181,13,' South_America capitals ','Capital of Paraguay?Asuncion<div><br /></div><div><img src="asuncion-paraguay.jpg" /></div><div><br /></div><div>[sound:rec1476205181.mp3]</div>','Capital of Paraguay?',3088135100,0,'');
CREATE INDEX ix_notes_usn on notes (usn);
CREATE INDEX ix_notes_csum on notes (csum);
COMMIT;
sqlite> 

At this point you are free to update the entries with standard sql commands.