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POThe forgotten assignment operator "=" and the commonplace ":="
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copied!<p>The documentation for PL/pgSQL says, that declaration and assignment to variables is done with <code>:=</code>. But a simple, shorter and <em>more modern</em> <sup>(see footnote)</sup> <code>=</code> seems to work as expected:</p> <pre><code> CREATE OR REPLACE FUNCTION foo() RETURNS int AS $$ DECLARE i int; BEGIN i = 0; WHILE NOT i = 25 LOOP i = i + 1; i = i * i; END LOOP; RETURN i; END; $$ LANGUAGE plpgsql; > SELECT foo(); 25 </code></pre> <p>Please note, that Pl/pgSQL can distinguish assignment and comparison clearly as shown in the line </p> <pre><code> WHILE NOT i = 25 LOOP </code></pre> <p>So, the questions are:</p> <ul> <li>Didn't I find some section in the docs which mention and/or explains this?</li> <li>Are there any known consequences using <code>=</code> instead of <code>:=</code>?</li> </ul> <p><strong>Edit / Footnote:</strong></p> <p>Please take the "more modern" part with a wink like in <a href="http://james-iry.blogspot.com/2009/05/brief-incomplete-and-mostly-wrong.html" rel="noreferrer">A Brief, Incomplete, and Mostly Wrong History of Programming Languages</a>:</p> <blockquote> <p>1970 - Niklaus Wirth creates Pascal, a procedural language. Critics immediately denounce Pascal because it uses "x := x + y" syntax instead of the more familiar C-like "x = x + y". This criticism happens in spite of the fact that C has not yet been invented.</p> <p>1972 - Dennis Ritchie invents a powerful gun that shoots both forward and backward simultaneously. Not satisfied with the number of deaths and permanent maimings from that invention he invents C and Unix.</p> </blockquote>

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