Re: Unclear about key_len in EXPLAIN output

2006-02-03 Thread James Harvard
At 11:09 am -0500 3/2/06, sheeri kritzer wrote: >The manual is large and vast, I couldn't find the text you quoted on >the page I sent. What page did you find that text on? It's the latter part of the second sentence from the same paragraph that you quoted in your e-mail. >As well, if the key th

Re: Unclear about key_len in EXPLAIN output

2006-02-03 Thread sheeri kritzer
The manual is large and vast, I couldn't find the text you quoted on the page I sent. What page did you find that text on? As well, if the key that EXPLAIN uses is multi-part, you would know from the length of the fields. You have to use some deductive reasoning, but I don't think it's really mur

Re: Unclear about key_len in EXPLAIN output

2006-02-02 Thread James Harvard
'That other statement' that I quoted is actually just part of the paragraph from the manual that you quoted! My point was that it doesn't say what units the key length is given in or explain _how_ to determine the number of parts used. However the more I think about it the more I see that it mu

Re: Unclear about key_len in EXPLAIN output

2006-02-02 Thread sheeri kritzer
according to: http://dev.mysql.com/doc/refman/5.0/en/explain.html "The key_len column indicates the length of the key that MySQL decided to use. The length is NULL if the key column says NULL. Note that the value of key_len enables you to determine how many parts of a multiple-part key MySQL actu

Unclear about key_len in EXPLAIN output

2006-02-01 Thread James Harvard
According to the manual "the value of key_len enables you to determine how many parts of a multiple-part key MySQL actually uses." However, it doesn't specify quite how one can determine that. It _looks_ like the number of bytes in the key (or key part) that is used - is that correct? TIA, Ja