intoOracle INSERT INTO : A Comprehensive Guide（oracleinsrt）

Anybody familiar with SQL understands the importance of INSERT INTO. It is, quite simply, one of the most useful statements in the language. It allows a user to insert one or more rows of data into a given table in a relational database, such as Oracle.

This tutorial serves as a comprehensive guide for learning how to use the INSERT INTO statement in Oracle. First, we will review the syntax of INSERT INTO and explain what it does. Next, we will discuss examples of how to use it, from simple single-row inserts to complex multi-table inserts. Finally, we will explore some performance tips and tricks that you can use when writing your INSERT INTO statements.

The syntax for the INSERT INTO statement is relatively straightforward. It has the following basic form:

INSERT INTO table_name (column1, column2, column3, … ) VALUES (value1, value2, value3, … );

The keyword INSERT INTO indicates that we are going to be inserting new data into the table. Next, we specify the table name. We then specify the columns we wish to insert into, followed by the VALUES keyword. Finally, we provide the new data values that will be inserted into the specified columns.

Now that we understand the syntax, let’s look at some examples of how to use this statement in Oracle. Let’s imagine we have a table called “students”, with the following schema:

STUDENT_ID number primary key,

FIRST_NAME varchar2(40),

LAST_NAME varchar2(40),

GRADE number

If we wanted to insert a single row of data into this table, we could use a statement like this:

INSERT INTO students

(student_id, first_name, last_name, grade)

VALUES

(1, ‘John’, ‘Doe’, 3);

This statement creates a new row in the “students” table with a student_id of 1, a first_name of “John”, a last_name of “Doe”, and a grade of 3.

In addition to single-row inserts, you can also use INSERT INTO to insert multiple rows of data into a table. This comes in handy if, for example, you need to quickly populate a table with a large amount of data. To do this, you would use a statement like this:

INSERT ALL

INTO students (student_id, first_name, last_name, grade)

VALUES (1, ‘John’, ‘Doe’, 3)

INTO students (student_id, first_name, last_name, grade)

VALUES (2, ‘Jane’, ‘Smith’, 4)

INTO students (student_id, first_name, last_name, grade)

VALUES (3, ‘James’, ‘Johnson’, 3)

INTO students (student_id, first_name, last_name, grade)

VALUES (4, ‘Jill’, ‘Adams’, 5)

SELECT * FROM dual;

This statement adds four rows of data to the “students” table in one go.

The INSERT INTO statement can also be used to insert data into multiple tables at once. This can be accomplished by writing a statement that involves multiple insert commands. For example:

INSERT INTO students

(student_id, first_name, last_name, grade)

VALUES

(1, ‘John’, ‘Doe’, 3);

INSERT INTO grades

(student_id, subject, grade)

VALUES

(1, ‘English’, 85);

INSERT INTO grades

(student_id, subject, grade)

VALUES

(1, ‘Math’, 95);

This statement inserts a row into the “students” table and also adds two rows of data into the “grades” table.

Finally, let’s look at some performance tips when using the INSERT INTO statement. Here are some tips to keep in mind:

• Use bulk inserts wherever possible. This means inserting multiple rows of data at once instead of one at a time. This can help improve performance.

• Consider using the PARALLEL hint if you need to insert a large amount of data. This hint can help improve performance by distributing the workload across multiple CPUs.

• If you don’t need to provide values for every column, use the keyword “DEFAULT”. This saves time and prevents unnecessary operations.

In conclusion, INSERT INTO is a powerful and versatile statement that is an essential part of any SQL programmer’s toolbox. With the proper syntax and a few performance tips, you can easily get up and running with using INSERT INTO in Oracle.