What Is WORA Form and How To Use It

For Impatient Men

Dont touch any buttons and menus - just press on QUERY. Experiment as you like, feel free.

Columns

Form generating program, so called CGI-script, produces its output ( document body, containing the form ) looking deeply into database internals.
For the given table program extracts information about all columns, aka fields, in this table - what are columns' names, what are internal types of those columns and what are their lengths.
Next, program has lists of database functions which could be applied to the fields you are planning to select.
This information is combined in such a way, that you can

Mark on the screen what field you wanna be extracted and which not,
What functions should be applied to each column to be selected.

Condition, aka "WHERE clause"

In the specialized language for communication with relational databases, SQL, you have possibilities to define conditions which should be met for the record to be extracted. Specific SQL jargon names it where clause.
SQL is very like to plain english, e.g.

	SELECT some_function(some_field FROM) some_table
		WHERE some_function(yet_another_field) "OPERATOR" "EXPRESSION"
			OR
		WHERE some_function(yet_another_field) "OPERATOR" "EXPRESSION"
			AND
		WHERE some_function(yet_another_field) "OPERATOR" "EXPRESSION"
			...

Things are a bit more complicated, but you supposed to catch the general idea.
Function, "EXPRESSION" and "OPERATOR" depend on yet_another_field type.
WORA has very simplificated notion of the where clause - all you can do is to define single yet_another_field with a single function applied to this field.
Naturally, only one "OPERATOR" and "EXPRESSION" available for one condition.

I've already seen, that char_field LIKE pattern causes great trouble.
It was rewritten to be more user friendly. See changes.
If you are a simple guy, just type substring.

To use full pattern matching enter string literal as it should be entered in SQLPLUS.
The same is true for string comparisons.

Misc

So called group functions (like SUM,COUNT) do exist. They are somewhat peculiar - you can't use usual function (or none) applied to one field and group function applied to another field in the same SQL statement. It should be balanced in that sense.
Dont worry, WORA will tell you what Oracle thinks about your typos and mistakes. Frankly speaking, database error descriptions ( which simply transferred from DB to you, dear user ) sometimes are very clear for John Dow, sometimes enigmatic :(

Examples

Lets imagine table all_names with several columns:

name - character
apartment - number
floor - number
phone - character

	select initcap(name), phone from all_names
		where floor > 100

will give capitalized names and phone numbers of all people living high, almost in the sky.

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