Tables and flat files have rows and columns of information., Scalability means a system can grow when demand does., Data persistence means data might be stored forever., A relational database links the information in different tables., A null value means there is no data., A logical schema outlines the structure of a database., Physical schema refers to the actual tables, columns and relationships created in the RDBMS., A row in a table is called a record., A column in a table is called a field., A primary key identifies a record uniquely., Constraints set limitations to prevent problems with a database., Queries are questions a database can answer., Non-structured data like pictures and documents don't fit into a database., Metadata is an example of semi-structured data., Two types of databases are document and key/value., Different types of access are manual, direct, programmatic, user interface and utility., Global or server permissions are usually only for an administrator account., Permissions can be granted, denied or revoked., The drop command deletes database objects., A database dump is a one-time backup of a database that exports the schema, tables, views with the data.,
0%
Understanding Databases (7.1)
Baham ko'rish
Baham ko'rish
Baham ko'rish
tomonidan
Jacaceres
Tarkibini tahrirlash
Chop etish
qo'shib qo'yish
Ko'proq
Tayinlashlar
Ilg'orlar ro'yxati
Ko'proq ko'rsatish
Kamroq koʻrsatish
Ushbu etakchilar jadvali hozirda xususiy. Uni ommaga etkazish uchun
Ulashish-ni
bosing.
Liderlar ro'yxati resurs egasi tomonidan o'chirib qo'yildi.
Ushbu etakchilar ro'yxati o'chirib qo'yilgan, chunki sizning variantlaringiz resurs egasidan farq qiladi.
Qaytish moslamalari
Oʻchirish
ochiq-oydin shablon. Etakchilar ro'yxati uchun ballar yaratmaydi.
Tizimga kirish talab qilinadi
Vizual uslub
Shriftlar
Obuna talab etiladi
Moslamalar
Namunani almashtirish
Hammasini koʻrsatish
Faoliyatni o'ynaganingizda ko'proq formatlar paydo bo'ladi.
Ochiq natijalar
Bogʻdan nusxa olish
Tez javob kodi
& Olib tashlash
Tahrirlashni davom ettirish:
?