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These are some common post restore processes:

  • Sync the logins and users
  • Validate the data is accurate
  • Notify the team/user community
  • Cleanse the data to remove sensitive data i.e. SSNs, credit card information, customer names, personal information, etc.
  • Change database properties i.e. recovery model, read-only, etc.

The wildcard character is %. If you want to query database with LIKE for all employees whose name starts with La.  the proper query with LIKE would involve ‘La%’. 

Relational tables have the following five properties:

  • Values are atomic.
  • Column values are of the same kind.
  • The sequence of columns is insignificant.
  • The sequence of rows is insignificant.
  • Each column must have a unique name.

De-normalization is the process of attempting to optimize the performance of a database by adding redundant data. It is sometimes necessary because current DBMSs implement the relational model poorly. A true relational DBMS would allow for a fully normalized database at the logical level, while providing physical storage of data that is tuned for high performance. De-normalization is a technique to move from higher to lower normal forms of database modeling in order to speed up database access.

ACID (an acronym for Atomicity Consistency Isolation Durability) is a concept that database professionals generally look for while evaluating relational databases and application architectures. For a reliable database, all four of these attributes should be achieved:

Atomicity is an all-or-none rule for database modifications.
Consistency guarantees that a transaction never leaves your database in a half-finished state.
Isolation keeps transactions separated from each other until they are finished.
Durability guarantees that the database will keep track of pending changes in such a way that the server can recover from an abnormal termination and committed transactions will not be lost.

  • Issue the RESTORE VERIFYONLY command to validate the backup.
  • Restore the backups as a portion of a log shipping solution.
  • Randomly retrieve tapes from off site and work through the restore process with your team to validate the database is restored in a successful manner.

  • Review the SQL Server error log for backup related entries.
  • Query the msdb.dbo.backupset table for the backup related entries.
  • Review the file system where the backups are issued to validate they exist.

Backups can be automated by using a cursor to loop through each of the databases and backup each one

Restores can also be automated by either looping over the files, reading from the system tables (backup or log shipping) or reading from a table as a portion of a custom solution.

1NF: Eliminate repeating groups
Make a separate table for each set of related attributes and give each table a primary key. Each field contains at most one value from its attribute domain. De-normalizing the database design allows for fewer joins with tables and foreign key requirements. This method is commonly used for Reporting and OLAP workloads.
2NF: Eliminate redundant data
If an attribute depends on only part of a multi-valued key, then remove it to a separate table.
3NF: Eliminate columns not dependent on the key If attributes do not contribute to a description of the key, then remove them to a separate table. All attributes must be directly dependent on the primary key. 
BCNF: Boyce-Codd Normal Form
If there are non-trivial dependencies between candidate key attributes, then separate them out into distinct tables.
4NF: Isolate independent multiple relationships No table may contain two or more 1:n or n:m relationships that are not directly related.
5NF: Isolate semantically related multiple relationships. There may be practical constraints on information that justifies separating logically related many-to-many relationships.
ONF: Optimal Normal Form
A model limited to only simple (elemental) facts, as expressed in Object Role Model notation.
DKNF: Domain-Key Normal Form
A model free from all modification anomalies are said to be in DKNF.
Note: These normalization guidelines are cumulative. For a database to be in the 3NF, it must first fulfill all the criteria of a 2NF and 1NF database.

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