Oracle 12c Database
GROUP BY functions?
AVG, COUNT, MEDIAN, MAX, MIN, SUM
Table structure
Aspect of columns, CREATE Table
Control transactions
COMMIT, ROLLBACK, SAVEPOINT, SET TRANSACTION, SET CONSTRAINT
CURRENT_DATE v SYSDATE
CURRENT_DATE shows the timezone difference in the timestamp where as SYSDATE only shows the time specific to the database's location.
JOINS
EQUIJOINS, NON-EQUIJOINS, SELF-JOINS, INNER-JOIN, FULL-OUTER-JOIN, LEFT-OUTER-JOIN, RIGHT-OUTER-JOIN, CROSS JOIN, NATURAL JOIN
Physical, Theoretical aspects of relational database
Flat files, Hierarchial, Network model Structure, Relational model, DBMS, Tuple, Relation, attribute, Attribute value, Domain, Entity
Conditional Expressions?
IF-THEN-ELSE
Subqueries
Inline view, Nested Subquery
DUAL table
It is a special one row, one column table present by default in Oracle and other database installations.
Salient Features of Oracle 12c Oracle cloud
Multi tenant Architecture, Smarter Data Storage.
What are the five types of a single row?
Numeric, Character, Data time, Conversion, General
What are the features of oracle 12c Database?
Pluggable Database, Process Threads, ILM capabilities, Temp. Undo, Row Pattern Matching, PL/SQL functions Defined in the SQL WITH Clause, Sequences can be used for Column Defaults, Explicit Null Insertion, Increased Size Limits, Query row limits and Row Offsets
Set Operators
SET, UNION ALL, UNION, INTERSECT, MINUS
Oracle servers implementation of RDBMS and object relational database management system.
Schema objects, SQL statements, Transaction management, Data Concurrency, Data Consistency, Data files, Control files, Online redo log files, Data blocks, Extents, Segments, Table space,
How to retrieve Data using the SQL SELECT statement
Select Statements, Using terms associated with SQL statements,
How to write multiple-row, single-row subqueries
Set Operations, Restrictions on set operations
Problems solved by subqueries
Single-row, Multiple-row, and Correlated subqueries
Conversion functions?
TO_CHAR, TO_NUMBER, TO_DATE, Format modifiers
connection pooling model
With connection pooling, the application server establishes a relatively small number of persistent database sessions and makes them available on demand (queuing requests if necessary) to a relatively large number of end-user sessions against the application server.