MODULE 3: SQL DML (Data Manipulation Language), Physical ...
MODULE 3: SQL DML (Data Manipulation Language), Physical Data Organization
PREPARED BY SHARIKA T R, SNGCE
PREPARED BY SHARIKA T R, SNGCE
SYLLABUS
? SQL DML (Data Manipulation Language) SQL queries on single and multiple tables, Nested queries (correlated and non-correlated), Aggregation and grouping, Views, assertions, Triggers, SQL data types.
? Physical Data Organization Review of terms: physical and logical records, blocking factor, pinned and unpinned organization. Heap files, Indexing, Singe level indices, numerical examples, Multi-level-indices, numerical examples, B-Trees & B+-Trees (structure only, algorithms not required), Extendible Hashing, Indexing on multiple keys ? grid files
PREPARED BY SHARIKA T R, SNGCE
Data-manipulation language(DML)
? The SQL DML provides the ability to query information from the database and to insert tuples into, delete tuples from, and modify tuples in the database.
Integrity
The SQL DDL includes commands for specifying integrity constraints that the data stored in the database must satisfy. Updates that violate integrity constraints are disallowed.
View definition
The SQL DDL includes commands for defining views.
Transaction control
SQL includes commands for specifying the beginning and ending of transactions.
PREPARED BY SHARIKA T R, SNGCE
Basic Retrieval Queries in SQL
? SQL has one basic statement for retrieving information from a database; the SELECT statement
? This is not the same as the SELECT operation of the relational algebra
? Important distinction between SQL and the formal relational model;
SQL allows a table (relation) to have two or more tuples that are identical in all their attribute values
Hence, an SQL relation (table) is a multi-set (sometimes called a bag) of tuples;
it is not a set of tuples SQL relations can be constrained to be sets by specifying PRIMARY KEY or UNIQUE attributes, or by using the DISTINCT option in a query
PREPARED BY SHARIKA T R, SNGCE
SELECT
FROM
WHERE ?
is a list of attribute names whose values are to be retrieved by the query
?
is a list of the relation names required to process the query
?
is a conditional (Boolean) expression that identifies the tuples to be retrieved by the query
................
................
In order to avoid copyright disputes, this page is only a partial summary.
To fulfill the demand for quickly locating and searching documents.
It is intelligent file search solution for home and business.
Related download
- lab 2 data definition language ddl eng alaa o shama
- chapter 6 introduction to sql structured query language
- module 3 sql dml data manipulation language physical
- database management systems lab
- uussiinngg ddddll ssttaatteemmeennttss
- introduction to ddl dml dcl
- data definition language ddl reference manual
- my sql worksheet 1
- lab 4 data definition language ddl
- 1 creating a relational database schema from er diagram
Related searches
- sql server data classification
- sql server data classification tool
- sql server data types
- sql datetime data type
- proc sql change data type
- sql azure data studio
- ces module 3 problem solving
- sql date data type format
- creative writing module 3 shs
- powershell module for sql server
- sql convert data to numeric type
- sql numeric data type size