When must you define constraints at the table level rather than the column level? ( refer to the tables in the JustLee Books database).

Q: xplain Local Descriptor Table?

A: Local descriptor table (LDT) : There are 3 different types of descriptor table  Global descriptor…

Q: A select procedure in a relational database can shrink a table's size by deleting columns that don't…

A: Answer is

Q: SOSL Query: Create a SOSL Query in salesforce to find the test keyword in the whole organization.…

A: Here we have to create an SOSL query in salesforce to find the test keyword. Here I have syntax for…

Q: What considerations should be made when determining whether or not to establish an index for a…

A: Introduction: After the CREATE NONCLUSTERED INDEX clause, give the index a name. You don't have to…

Q: Create the following queries for the “books” database. For each query make sure to only include…

A: SELECT COUNT(TITLE_ID) AS "# of long books" FROM TITLES WHERE TITLES.PAGES>=450 GROUP BY TYPE;

Q: Alter the MAINTENANCE_TYPES table to include a new column named MAINTENANCE_PRICE of type FLOAT.

A: ALTER TABLE MAINTENANCE_TYPES ADD MAINTENANCE_PRICE float;   Alter Query is used to change the DDL…

Q: Refer the below schema and create the SCHEDULE. Column Constraint Constraint name Reference table -…

A: Required:    By following the given schema create the SCHEDULE table   Create function is used to…

Q: Using the software.subscription table, pull all columns for subscriptions that have been cancelled.…

A: For the given database, if the user wants to select all the columns by giving the condition that the…

Q: You’re creating a new table consisting of three columns: Col1, Col2, and Col3. Col1 should be the…

A: It requires only two constraints, one PRIMARY KEY constraint for Col1 and one NOT NULL constraint…

Q: The Car Maintenance team wants to update the price of Oil Change to 75. In addition, they will no…

A: We need to write the MYSQL query to update the price of Oil Change to 75 and remove the maintenance…

Q: Which restriction may be used to ensure that a book's category is included when it is added to…

A: Introduction: Inventory refers to the raw materials utilized in manufacturing and the finished…

Q: What is the maximum number of PRIMARY KEY constraints allowed for a table? ( refer to the tables in…

A: Primary key constraints The primary key constraint uniquely identifies each record in a table.…

Q: Create a query that returns all appointments that were either cancelled, or patients were No Show in…

A: 4) SELECT Doctor.Doctor_FName, Doctor.Doctor_LName, Patient.Patient_First_Name,…

Q: Create the Student table with following details: Data type Number Varchar(25) Field Constraint Sid…

A: We are assuming that the field book_id references a table by name of Book which has book_id as its…

Q: How many NOT NULL constraints can be created at the table level by using the CREATE TABLE command? (…

A: Utilizing the CREATE TABLE command, "0" NOT NULL constraints can be created at the table level.…

Q: When is an index appropriate for a table?

A: Index: The index is used to access the data from the database speedily. Syntax of creating an index:…

Q: The first requirement: Using the SQL language, transform the following entity model into tables in…

A:

Q: What is the difference between a UNIQUE and a PRIMARY KEY constraint? (See the tables in the JustLee…

A: Key in Database: Key constraint is used to identify the records uniquely in the table. The Table may…

Q: What is the difference between disabling a constraint and dropping a constraint? ( refer to the…

A: Difference between disabling a constraint and dropping a constraint: The differences are given as a…

Q: Refer the below schema and create the SCHEDULE. Column Datatype Size Constraint Constraint name…

A: Brief Introduction:We are provided with the whole schema of the Bus Booking System in which we are…

Q: Enclosure Number ENCLOSURE Date Type Location Size Built Animal Animal Number Species Name Gender…

A: Relationship diagram for the central zoo database is drawn below

Q: Many queries search by the number of days to ship (number of days between the order and shipping…

A: Explanation: The below query index the data based on ship days. Then sorts this data on the bases…

Q: What is the difference between a UNIQUE and a PRIMARY KEY constraint? (See the tables in the JustLee…

A: Introduction: When creating a table, a primary key is used to identify each row in the table, while…

Q: Which are the primary key in the following tables

A: A primary key is the column or columns that contain values that uniquely identify each row in a…

Q: do this  Following tables support the database of a shopping store. The schema contains four tables…

A: here have to determine about sql query from given problem.

Q: 7. Create the BOOKS table: Column Name Data Type Size Constraints BookID Number 5 PRIMARY KEY NOT…

A: SQL stands for Structured Query Language.

Q: What is the primary key for the APARTMENTS table? (It may be a composite key involving 2 or more…

A: The question asks to identify the primary keys and foreign keys for the "APARTMENTS" and "RENTERS"…

Q: Show accumulated high salary and low salary from SALGRADE table.  Display the highest, lowest, sum,…

A: Given: Show accumulated high salary and low salary from SALGRADE table.

Q: Below is part of a Student database. The primary keys are highlighted in bold. Student (studNo,…

A: The below sql statements are to calculate the amount to be paid for a student for all courses he/she…

Q: In the process of query optimization, query cost refers to: A) How long it takes to execute a query.…

A: Query optimization is a process in database management systems (DBMS) that seeks to determine the…

Q: ery evaluation plan? How do you measure

A: Query evaluation plan

Q: Which of these is more important, Primary Key or Unique? In the JustLee Books database, you may look…

A: Given: We  need to  explain  about  Primary key   and unique key.

Q: With the use of a group function, which clause can be used to restrict or filter the groups returned…

A: To be determine: Which clause can be used to restrict or filter the groups returned by a group…

Q: In the BOOK_PRICING database, the Category field should be marked as obsolete. Make sure the column…

A: An obsolete playing field in a database is no longer in use or needed. These are often fields that…

Q: Under what circumstances should you not create an index for a table?

A: When the table is updated regularly or searches generally return more than 10% of the table rows in…

Basic SQL Queries

Structured Query Language is the full form of SQL. It is a high-level language used to communicate with a relational database. It is used for creating, storing and accessing contents of a relational database. SQL is used to write the queries which are executed using database engines like Oracle, SQL Server and so forth.