These are attributes of one table that have matching values in a primary key in another table, allowing for relationships between tables.
Latest Answer : Foreign Keys are keys used in a table as an attribute and are primary keys of some other table ...
Describe the elements of the SELECT query syntax. SELECT element FROM table WHERE conditional statement?
Explain the use of the WHERE clause. WHERE is used with a relational statement to isolate the object element or row.
Joins, unions and nested selects are used to retrieve data.
Latest Answer : The two tables has to be linked.EXEC SQL
SELECT A.EMP_ID, B.WAGE FROM Table1 A, Table2 B WHERE A.EMP_ID = B.EMP_ID
AND A.EMP_ID = ...
DDL is data definition language and DML is data manipulation language. DDL statements are CREATE, ALTER, TRUNCATE. DML statements are SELECT, INSERT, DELETE and UPDATE.
Latest Answer : DDL(data definition language)DDL Statement are · Create· Alter and· Drop DML(data ...
Group by controls the presentation of the rows, order by controls the presentation of the columns for the results of the SELECT statement.
Latest Answer : Group By forms Groups (of course), but this means it also SORTS; but it will also retrieve a DISTINCT RECORD SETORDER BY Sorts by the columns included in the Statement, and does not retrieve DISTINCT Records.Neither determines the order of the columns ...
The explain statement provides information about the optimizer's choice of access path of the sql.
Latest Answer : The EXPLAIN statement obtains information about access path selection for an explainable statement. A statement is explainable if it is a SELECT or INSERT statement, or the searched form of an UPDATE or DELETE statement.The information obtained is placed ...
An embedded sql statement may return a number of rows while the programming language can only access one row at a time. The programming device called a cursor controls the position of the row.
Latest Answer : hi friends, In DB2 actually we use CURSOR when there are more than one row to be fetched in a SELECT statement. ...
Referential integrity refers to the consistency that must be maintained between primary and foreign keys, ie every foreign key value must have a corresponding primary key value.
Latest Answer : the relation of the primary key of a base table with foreign key of the reference table is known as referential integriety. ...
To maintain the integrity of DB2 objects the DBD permits access to only on object at a time. Lock contention happens if several objects are required by contending application processes simultaneously.
