D4 – Declarative Data-Driven Documents

Re:D4 – Declarative Data-Driven Documents by morgante on Tuesday July 19, 2016 @12:19AM (#12119616)

Yes, SQL is declarative.

But you still "SELECT" something to look at. A SELECT statement is, by itself, sufficient to get something to happen (for results to be fetched).

On the other hand, a D3 enter() does absolutely nothing by itself. You must do further calls for it to have any impact.

This is very off topic and ridiculous.

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Re:D4 – Declarative Data-Driven Documents by jdmichal on Tuesday July 19, 2016 @10:20AM (#12121914)

OK, if a SELECT statement is sufficient by itself, surely you can tell me the results of this:

    SELECT * FROM stuff WHERE thing=2

Of course you can't. Because every declarative process has two main steps: declare and execute. SELECT and enter() both only declare; they must then be executed against data in an engine to produce a result.

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Re:D4 – Declarative Data-Driven Documents by Retra on Wednesday July 20, 2016 @12:51AM (#12126969)

What we mean when we say "SQL is declarative" is that it doesn't provide instructions on how to carry out a task, and instead only provides a description of the outcome of the task, once it's been carried out. SELECT is declarative because it doesn't tell the computer how to do a query. SELECT tells the interpreter what you want not how to get it.

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