Addition of new rows with SELECT

To pull values into a table from one or more other tables, you can use a SELECT clause in the INSERT statement. The select clause can insert values into some or all of the columns in a row.

Inserting values for only some columns can be useful when you want to take some values from an existing table. Then, you can use the UPDATE statement to add the values for the other columns.

Before inserting values for only some of the columns in a table, make sure that either a default exists, or that you specify NULL for the columns into which you are not inserting values. Otherwise, an error appears.

When you insert rows from one table into another, the two tables must have compatible structures—that is, the matching columns must be either the same data types or data types between which SQL Anywhere automatically converts.

Inserting data into some columns

Inserting data from the same table

You can insert data into a table based on other data in the same table. Essentially, this means copying all or part of a row.

For example, you can insert new products, based on existing products, into the Products table. The following statement adds new Extra Large Tee Shirts (of Tank Top, V-neck, and Crew Neck varieties) into the Products table. The identification number is 30 greater than the existing sized shirt:

INSERT INTO Products
SELECT ID + 30, Name, Description,
    'Extra large', Color, 50, UnitPrice, NULL
FROM Products
WHERE Name = 'Tee Shirt';

Example

If the columns are in the same order in both tables, you do not need to specify column names in either table. For example, suppose you have a table named NewProducts that has the same schema as the Products table and contains some rows of product information that you want to add to the Products table. You could execute the following statement:

INSERT Products
SELECT *
FROM NewProducts;

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