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SQL BETWEEN Operator Example.

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SQL BETWEEN Operator Example SQL BETWEEN Operator Example The BETWEEN operator in SQL selects values within a given range. The values can be numbers, text, or dates. It is inclusive, which means it includes the beginning and ending values in the range. Example Usage Consider a table named Employees with the following data: ID Name Age 1 John Doe 28 2 Jane Smith 34 3 Emily Johnson 40 To find employees whose ages are between 30 and 35, you would use the following SQL query: SELECT * FROM Employees WHERE Age BETWEEN 30 AND 35; This query will return: ID Name Age 2 ABC Kumar 34
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SQL IS NOT NULL.

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SQL IS NOT NULL Explanation Understanding the SQL IS NOT NULL Condition The IS NOT NULL condition in SQL is used to check for non-null values in a specified column. It helps in filtering the data by excluding rows where the column's value is NULL. Go To Download Examples Consider a database table named Employees with the following columns: Id - Employee's ID Name - Employee's Name Department - Department where the employee works Email - Employee's Email Address To select all employees who have an email address (i.e., where the email address is not null), you would use the following SQL query: SELECT * FROM Employees WHERE Email IS NOT NULL; This query returns all records from the Employees table where the Email column does not contain NULL values. Combining Conditions You can combine IS NOT NULL with other conditions to make more spec
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SQL WHERE NOT in SQL.

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SQL WHERE NOT Explanation Understanding the SQL WHERE NOT Clause The WHERE NOT clause in SQL is used to filter the results returned by a query based on conditions that do not match specified criteria. Essentially, it excludes records that match the condition. It is the logical opposite of the conditions that are typically specified with the WHERE clause. Examples Consider a database table named Employees with the following columns: Id - Employee's ID Name - Employee's Name Department - Department where the employee works Salary - Employee's Salary To select employees who do not work in the 'Sales' department, you would use the following SQL query: SELECT * FROM Employees WHERE NOT Department = 'Sales'; This query will return all employees whose Department is not 'Sales'. It effectively excludes all 'Sales' department employees
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SQL OR Clause Example.

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SQL OR Clause Example SQL OR Clause The OR operator is used in SQL to combine multiple conditions in a WHERE clause. It allows the SQL query to fetch records if any of the conditions specified are true. Example Usage of OR Consider a database table named Employees with the following columns: EmployeeID - An identifier for the employee. Name - The name of the employee. Age - The age of the employee. Department - The department where the employee works. We want to find all employees who are either 30 years old or work in the 'Sales' department. The SQL query would look like this: SELECT * FROM Employees WHERE Age = 30 OR Department = 'Sales'; Explanation of the Query The query selects all columns from the Employees table where the Age is 30 or the Department is 'Sales'. The OR operator allows the query to f
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Understanding the WHERE Clause in SQL Queries

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Understanding the WHERE Clause in SQL Queries Understanding the WHERE Clause in SQL Queries Welcome to our blog post on SQL! Today, we're focusing on one of the most essential aspects of writing SQL queries - the WHERE clause. This clause is critical for filtering records in a database to fetch only those that meet specific criteria. What is the WHERE Clause? The WHERE clause is used in SQL to filter records, making it possible to specify conditions on columns that must be met for a row to be included in the results. Without the WHERE clause, an SQL query returns all rows from the tables mentioned in the SQL statement. However, if you want to retrieve only a subset of those rows that fulfill a particular criterion, you would use the WHERE clause. Basic Syntax The basic syntax of the WHERE clause in a SELECT statement is as follows: SELECT column1, column2, ... FROM table_name WHERE condition; Example Queries Using
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Relationship(cont........)

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Relationships in Database Relationship Relationship is nothing but an association among two or more entities. Entities take part in relationships. We can often identify relationships with verbs or verb phrases. As shown in Fig. 12.1 One-to-One Relationships One-to-Many Relationships Many-to-One Relationships Many-to-Many Relationships Fig. 12.1 Home Previous
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Attributes(Cont.............)

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Attributes and Relational Data Models in ERP Systems ERP Management System - Attributes and Relational Data Model Attributes Attributes are single-valued properties of either an entity-type or a relationship-type, such as last name, first name, MIS, address, and birth date. Fig. 11.1 Relational Data Model The relational data model provides conceptual tools to design the database schema of a relational database. It describes the data, relationships between that data, data semantics, and constraints on the data in the relational database. Fig. 11.2 Previous Next
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