Database-Basic Concepts

Database-Basic Concepts
a basic concept
Table:
Columns are called fields
Rows are called records

Second System database
Master: All the system information, the location of all the other databases

tempdb: Temporary worksheets, each restart rebuild

Model: models, creating blank databases as templates

MSDB: Provides a database agent, Dispatches alerts, Jobs, and records operations that are used by

The system database is self-brought and must exist

Three database files:
A database file can have one or more transaction log files
Primary database File
Secondary database file

two transaction log files:
One transaction log file has only one database file

three file groups
Primary filegroup and Secondary filegroup

Four common binary data types
Binary (50): Fixed length
varbinary (MAX): variable length
Image: Storing the binary of an image

five commonly used text data types
Text: Long text information
ntext: Long text with variable length
CHAR (10): fixed length, 8000
varchar (MAX): variable-length non-Unicode data
nvarchar (MAX): variable-length Unicode data
NCHAR (10): fixed-length Unicode data
Datatime: Date Time

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Database-Basic Concepts