SQL Command Processor

SQL Workshop gives the user access to the SQL Command Processor.   It is here that any SQL statement within the rights and permissions of the HTML DB user can be typed in and executed.  Any SQL statement or PL/SQL block can be entered and executed.   The screen is divided between the statements entered by the user and the results of the statement after execution.  The statements can be a SELECT, an UPDATE, a DELETE, INSERT, CREATE TABLE, GRANT, or any other command.  It is a great interface that allows users to do exactly what they need to do.  Figure 5.10 shows the default display of the SQL Command processor.

It is a simple matter of entering the statement the user wishes to run and then executing it.   The statements can be executed either by pressing the Run button or by pressing the key combination CTRL+Enter.   I typically use the CTRL+Enter because my hands are already on the keyboard.   In Figure 5.11, a simple SELECT statement has been entered into the SQL Command processor and executed by pressing CTRL+Enter.  The results are shown in the results section of the screen.   The Autocommitand Display items at the top of the processor might be unfamiliar.   After each statement is executed, a commit will be issued depending on whether the Autocommit checkbox is checked or not.  This will save users from having to commit the data after an INSERT, UPDATE, or DELETE.    The Display drop down offers the option of how many rows to display after a Select statement.   To see more rows than which is shown, simply choose a higher number and re-run the statement.

There are also different tabs of the results section.  The following table contains an explanation of each:

TAB	DESCRIPTION
Results	Shows the results of the SQL or PL/SQL that have been entered.
Explain	Run the Explain Planon the SQL statements that are in use.  See the detail explanation later in this chapter.
Describe	Describes the structure of a table.
Saved SQL	These are saved SQL statements that all the developers can use.  Typically these are saved without values in the statement.  These would be supplied when needed.
History	HTML DB will save the last 120 commands that have been run.  The history can be used to recall the statement to run again.

For practice, create a table using the SQL Command processor.  The following create_easy_products.sql script shows the CREATE TABLE command for a table called  products.  

This statement can simply be typed into the SQL Command processor and executed.  Also, the create_easy_products.sql file from the online code depot can be used and executed.  Figure 5.12 shows what this step looks like.  Assuming all went well, the Table Created message will be displayed.  Very simple!  If the syntax of the command is incorrect, an error statement will point the user to their mistake.   Those familiar with other Oracle products will recognize these errors as the default Oracle errors.

Figure 5.13 shows the execution of an INSERT statement to add data to the table.