From:       To:      

Filtering data during the conversion

It is very common situation when you do not need to migrate the entire table to another database format but just a part of it. Intelligent Converters offers smart and flexible solution for such situations. Now our products allow users to filter data via SQL SELECT-queries. With this feature, you can select particular columns or data subset or simply rename columns in the resulting table. Below there are some examples of using queries for different purposes. Assume that we have MySQL table "Table1" defined as below:

   Table1(
	ID INT NOT NULL AUTO_INCREMENT, 
	FName VARCHAR(50),
	LName VARCHAR(50), 
	Birthday DATE, 
	Notes TEXT
   );

Example 1. Convert certain records.

SELECT * FROM Table1 WHERE ID > 1000

Example 2. Select and rename certain columns.

SELECT FName as FirstName, LName as LastName FROM Table1

Example 3. Skip records containing NULL values.

SELECT * FROM Table1 WHERE Notes IS NOT NULL

Example 4. Merge two tables.

Assume, you have two tables defined as follows:

   ProductLines(
	productline VARCHAR(50), 
        description VARCHAR(1000), 
	image       MEDIUMBLOB
   );                              
   Products(
	code        VARCHAR(15), 
	name        VARCHAR(70), 
	productline VARCHAR(50), 
	vendor      VARCHAR(50), 
	descroption TEXT, 
	quantity    SMALLINT, 
	price       DOUBLE
   );

If you want to get product code and product name from the "Products" table and description of product lines from the "ProductLines" table, it is possible to be done using the following query:

SELECT code,
       name,
       description
FROM Products T1
INNER JOIN ProductLines T2 ON T1.productline = T2.productline;

As you can see, SELECT-query is a powerful feature that allows you to precisely control the data for converting. With this feature it is so easy to arrange incremental conversion and migrate exact data you wish. It would be definitely useful for daily backup tasks and similar procedures requiring partial data migration.