Sesiones de PyR

Anybody explain the below lines in simple language so that i can understand.
//sql
1 Voto
1 Respuesta
10th Apr 2017, 7:40 PM
T Karthikeyan
T Karthikeyan - avatar
What is the difference b/w unique and primary key?
//sqlconstraints
4 Votos
2 Respuestas
10th Apr 2017, 4:54 PM
T Karthikeyan
T Karthikeyan - avatar
En tendencia hoy
How many time I can use sololearn trial mode?
1 Votes
Ошибка в приложении Sololearn
1 Votes
Is anyone else experiencing this Sololearn issue?
0 Votes
NEO V2.0
1 Votes
Did sololearn helped you to get easier a job?
1 Votes
Hello guys,
1 Votes
Sololearn course
1 Votes
solo learn program issue - iPhone?
1 Votes
Python
0 Votes
Bug sur le deuxième cours de python
1 Votes