UPDATE Table1 SET unique_column = unique_column + 1 WHERE unique_column = 55 in Java

Paint Data Matrix in Java UPDATE Table1 SET unique_column = unique_column + 1 WHERE unique_column = 55
UPDATE Table1 SET unique_column = unique_column + 1 WHERE unique_column = 55
DataMatrix Generation In Java
Using Barcode encoder for Java Control to generate, create Data Matrix 2d barcode image in Java applications.
Microsoft and Sybase call this the "deferred update" and also apply it for this situation:
Bar Code Printer In Java
Using Barcode creation for Java Control to generate, create bar code image in Java applications.
INSERT INTO Table1 SELECT * FROM Table1
Barcode Decoder In Java
Using Barcode recognizer for Java Control to read, scan read, scan image in Java applications.
A data change should not cause changes to any variable-length columns Even if the new value is shorter or the same length as the old value, the DBMS will adopt a pessimistic strategy on the assumption that a migration could occur For example, Microsoft and Sybase will treat the change as an out-of-place update However, if the total row size ends up shorter after the data change, the effects are less bad There should be no INSERT/UPDATE/DELETE trigger at all, or at least there should be no trigger that affects the same row that's being changed The problem is that data-change triggers need "before" and "after" copies of the data, and the DBMS has to produce extra information in the log file so that the "before" and "after"copies contain static information The changed column should not be in a primary key That's especially so if the primary key is the cluster key for a clustered index There should be no replication There should be only one table in the data-change statement Watch out for views containing subqueries that refer to other tables When several columns are changed, they should be contiguous or nearly contiguous Remember that columns are not always in the same order that you specify in the CREATE TABLE definition, because some DBMSs shift variable-length columns to the end of the row The WHERE clause of an UPDATE statement should not contain a reference to a column that's changed in the SET clause That is, avoid statements like:
Data Matrix 2d Barcode Creator In Visual C#
Using Barcode creation for VS .NET Control to generate, create Data Matrix image in .NET framework applications.
UPDATE Table1 SET indexed_column = indexed_column + 1 WHERE indexed_column >= 0
Data Matrix 2d Barcode Printer In .NET
Using Barcode creator for ASP.NET Control to generate, create Data Matrix ECC200 image in ASP.NET applications.
Such statements can confuse a DBMS that retrieves and processes rows in one pass, instead of getting the entire set of matching rows before processing the first one Consider what would happen with this example if all rows contain the value 0 in indexed_column
Making ECC200 In .NET
Using Barcode generator for .NET framework Control to generate, create Data Matrix image in VS .NET applications.
The SET clause of an UPDATE statement should not change columns that have just been used in a SELECT statement SELECT statements are pooled in a global area (for example, in Oracle's SGA) so that repetitions of the same SELECT can bypass the optimizer the DBMS just passes back the same result set The updating of critical columns invalidates this plan
Making Data Matrix ECC200 In Visual Basic .NET
Using Barcode encoder for .NET framework Control to generate, create Data Matrix ECC200 image in Visual Studio .NET applications.
In closing, let's look at a "tip" we've seen that is a really bad idea Consider this SQL statement:
Barcode Generator In Java
Using Barcode creation for Java Control to generate, create barcode image in Java applications.
UPDATE Table1 SET column1 = column1 WHERE column2 = 5
Creating UCC - 12 In Java
Using Barcode generation for Java Control to generate, create EAN 128 image in Java applications.
The trick in this statement is that you can get a count of the rows WHERE column2 = 5 because data-change statements always return a count of the number of rows affected But it's smarter and quicker to use good old COUNT(*)
Data Matrix 2d Barcode Encoder In Java
Using Barcode generator for Java Control to generate, create Data Matrix ECC200 image in Java applications.
The Bottom Line: Ugly Updates
Printing Barcode In Java
Using Barcode encoder for Java Control to generate, create bar code image in Java applications.
Put related and frequently done data-change statements into triggers and/or stored procedures
Encoding ANSI/AIM Code 128 In Java
Using Barcode creation for Java Control to generate, create Code 128C image in Java applications.
A data change should affect only one row if a UNIQUE-indexed column is changed A data change should not cause changes to any variable-length columns A data change should not affect a primary key When you're doing a data change, there should be no INSERT/UPDATE/DELETE trigger at all, or at least no trigger should affect the same row that's being updated There should be no replication Only one table should be referenced in a data-change statement When several columns are updated, they should be contiguous or nearly contiguous The WHERE clause of an UPDATE statement should not contain a reference to a column that's changed in the SET clause An UPDATE SET clause should not change columns that have just been used in a SELECT statement
UPC - E1 Creator In Java
Using Barcode drawer for Java Control to generate, create Universal Product Code version E image in Java applications.
FETCH and Data Changes
Barcode Drawer In .NET
Using Barcode maker for ASP.NET Control to generate, create bar code image in ASP.NET applications.
It's common practice to fetch a row, then UPDATE it with an UPDATE WHERE CURRENT OF <cursor> statement, or to fetch a row, then DELETE it with a DELETE WHERE CURRENT OF <cursor> statement Such techniques are unfriendly in multiuser environments If it's predictable that a data change will happen after a fetch, then:
Code-39 Creation In .NET Framework
Using Barcode creator for .NET framework Control to generate, create Code 39 Extended image in VS .NET applications.
You can incorporate the prediction in the WHERE clause so that the selection and data change take place together You can incorporate the prediction in a trigger so that the data change becomes situationally dependent
Barcode Generator In Visual C#
Using Barcode encoder for Visual Studio .NET Control to generate, create bar code image in .NET applications.
In short, you don't want to follow this procedure:
Drawing Data Matrix ECC200 In Visual Basic .NET
Using Barcode encoder for VS .NET Control to generate, create Data Matrix image in .NET framework applications.
Drawing Barcode In VB.NET
Using Barcode generator for .NET framework Control to generate, create barcode image in VS .NET applications.
Draw USS-128 In VS .NET
Using Barcode maker for ASP.NET Control to generate, create EAN 128 image in ASP.NET applications.