Explain the Difference between INSERT and UPDATE in SQL?

SQL is a programming language developed for extracting information from and updating a database. Moreover, SQL also performs various operations like managing data in a relational database management system (RDBMS).

The major difference between INSERT and UPDATE within SQL is that Insert is useful for adding new records within the table whereas Update is useful for changing the existing records in the table. Sql server dba training helps you to learn more effectively.

The INSERT and UPDATE are the DML (Data Manipulation Language) commands in SQL that help to modify data in the table. Ultimately, Insert helps to add one or more rows in the table and the Update values to the table.

Advantages of SQL:

SQL contains many advantages that make it popular and high in demand. It is a more reliable and efficient language useful for communicating with the database. The following are a few of the advantages of SQL:

No Coding Skills –

For data recovery, a huge number of lines of code is not required. All basic keywords like SELECT, INSERT INTO, UPDATE, etc are useful, and also the syntax rules are not complex in SQL. This feature makes it a user-friendly language among others.

Faster Query Processing –

A huge amount of data is recovered quickly and efficiently. Moreover, operations like insert, delete, and modification of data is also done in almost less time.

Standardized Language –

Due to documentation and long initiation over the years, it provides a constant platform to all its users globally.

Interactive Language –

The SQL language is very easy to learn and understand. Moreover, answers to complex queries can be received in very little time.

Update and Insert in SQL

Let us check the useful differences in Update and Insert.

Update in SQL

The UPDATE command is useful to modify the existing records within a table. We can also use it with the WHERE clause to modify a specific record. An update is also known as a DML statement. Below is the syntax for an “update” statement.

· UPDATE tableName

· SET column1Name=>value1; column2Name=>value2, ….

· WHERE columnXName=>some Value

The above example explains; tableName should be replaced with the name of the table that the user wants to change the records. The column1Name, column2Name under the SET clause are the names of the columns in the table where the values of the record that needs to be changed.

The value1 & value2 are the new values that should be inserted within the record. Moreover, the WHERE clause defines the set of records that need to be updated within the table. Besides, the WHERE clause could also be removed from the UPDATE statement. Hence, all the records in the table would be updated with the values given in the SET clause. Learn SQL server dba online course for more skills and techniques.

Example

Let’s understand the CUSTOMERS table having the following records −

EmpID I Emp Name I Emp Age I Add I Pay

· 1 Krishna — 22 — Ahmedabad — 2000.00

· 2 Khaitan — 25 — Chennai — 1500.00

· 3 Kaushik — 23 — Cuttack — 2000.00

· 4 Razak — 25 — Mumbai — 6500.00

· 5 Raj — 27 — Raigunj — 8500.00

· 6 Kamal — 23 — MP — 4500.00

· 7 Moti — 24 — Indore — 10000.00

The below mentioned query will update the ADDRESS for a customer whose ID number is 5 in the table.

· SQL> UPDATE CUSTOMERS

· SET ADDRESS = ‘Bhopal’

· WHERE ID = 5;

Now, the CUSTOMERS table includes the following records as mentioned −

EmpID I Emp Name I Emp Age I Add I Pay

· 1 Krishna — 22 — Ahmedabad — 2000.00

· 2 Khaitan — 25 — Chennai — 1500.00

· 3 Kaushik — 23 — Cuttack — 2000.00

· 4 Razak — 25 — Mumbai — 6500.00

· 5 Raj — 27 — Raigunj — 8500.00

· 6 Kamal — 23 — MP — 4500.00

· 7 Moti — 24 — Indore — 10000.00

Insert in SQL

Within SQL command, Insert is useful for inserting a new row to an existing table. It’s a DML statement too. The commands that are useful to maintain data without changing the database schema are called DML statements. Moreover, there are two options to write an Insert statement.

One format defines the names of the columns and the values that need to be inserted as below.

· INSERT INTO — tableName (column1Name, column2Name ….)

· VALUES — (value1, value2, …);

The other format does not mention the names of the column that the values need to be inserted.

· INSERT INTO tableName

· VALUES (value1, value2, …);

If the user is adding values for all the columns of the table, he doesn’t need to mention the column names within the SQL query. Although, he should make sure the order of the values must be in the same order as the columns in the table.

Example

The below statements would build 6 records within the CUSTOMERS table.

· INSERT INTO CUSTOMERS (ID,NAME,AGE,ADDRESS,SALARY)

· VALUES (1, ‘Krishna’, 32, ‘Ahmedabad’, 2000.00 );

· INSERT INTO CUSTOMERS (ID,NAME,AGE,ADDRESS,SALARY)

· VALUES (2, ‘Khaitan’, 25, ‘Chennai’, 1500.00 );

· INSERT INTO CUSTOMERS (ID,NAME,AGE,ADDRESS,SALARY)

· VALUES (3, ‘Kaushik’, 23, ‘Cuttack’, 2000.00 );

· INSERT INTO CUSTOMERS (ID,NAME,AGE,ADDRESS,SALARY)

· VALUES (4, ‘Razak’, 25, ‘Mumbai’, 6500.00 );

· INSERT INTO CUSTOMERS (ID,NAME,AGE,ADDRESS,SALARY)

· VALUES (5, ‘Raj’, 27, ‘Raigunj’, 8500.00 );

· INSERT INTO CUSTOMERS (ID,NAME,AGE,ADDRESS,SALARY)

· VALUES (6, ‘Kamal’, 22, ‘MP’, 4500.00 );

Here, you have the option to create a record in the CUSTOMERS table by using the second syntax as shown under.

· INSERT INTO CUSTOMERS

· VALUES (7, ‘Moti’, 24, ‘Indore’, 10000.00 );

All the above statements would present the below records in the CUSTOMERS table is presented under.

EmpID I Emp Name I Emp Age I Add I Pay

· 1 — Krishna — 22 — Ahmedabad — 2000.00

· 2 — Khaitan — 25 — Chennai — 1500.00

· 3 — Kaushik — 23 — Cuttack — 2000.00

· 4 — Razak — 25 — Mumbai — 6500.00

· 5 — Raj — 27 — Raigunj — 8500.00

· 6 — Kamal — 23 — MP — 4500.00

· 7 — Moti — 24 — Indore — 10000.00

Wrapping Up

Thus, we have gone through the difference between the INSERT and UPDATE DML commands in SQL. The name Insert reveals that something has to put in like data and the Update reveals that changing the existing data to get the latest results. Using these queries anyone can easily make any input and update to the records within systems. To get more insights on SQL queries, one can go through the SQL database administrator training.