Sequential read of MySQL Database

Montgomery

Can anyone suggest a quick and easy way to access the next row of a MySQL database. The column is varchar and I want to be able to go from fileds beginning with "a" to those beginning with "b" etc.

I cannot think of a way to do it using select, do I have to use mysql_row_seek and tell ?

Thanks in advance

Iain

Norman_Graham

Hi Iain

Maybe somebody else understands this, but I think you'll need to explain what you want to do. What do you mean by "go from a to b"? Perhaps if you post some code or at least explain what kind of functionality you want, it might make things clearer.

Whereabouts in Scotland you at?

Norm

Montgomery

I want to go backwards and forwards through a varchar column in alphabetical onrder.

Born Glasgow, live livingston.

Norman_Graham

Hi Iain

Do you want to loop through your DB table alphabetically? The query syntax contains the ORDER BY command, e.g.

SELECT * FROM mytable ORDER BY myfield ASC;
// You can also use DESC to go from Z to A

This orders the results alphabetically, if it's a TEXT/CHAR column, and numerically if it's an INT/FLOAT column.

Is that what you were looking for?

Norm

PS: Born Glasgow, live Berlin

Montgomery

Norman,

That is what I thought I should do.

The problem I have is I want to start at a certain point and then look only at the next one insequence. How can I do a select which will give me a small number rather than going from the start of the selection all the way Though. The number in the table will exceed 10,000 and I thougjt the time taken and the use of memory might slow it ut considerably.

I will probably do the above unless you have any better short cut.

Thanks for the feedback, most appreciated.

Iain

Born and brought up in sunny Govan.

Norman_Graham

Hi Iain

That should be no problem. You want the LIMIT command:

"SELECT * FROM mytable ORDER BY myfield ASC LIMIT 5";
// Retrieve rows 1-5

"SELECT * FROM mytable ORDER BY myfield ASC LIMIT 5, 5";
// Retrieve rows 6-10

HTH

Norm

Born and brought up in tropical Scotstoun 😃

Montgomery

Norman,

My final question is how do I get the number at which to start.

ie Limit x,y what is x

Thanks in advance.

Iain

I lived in London for 25 years. Coming back is the best thing I ever did.

Norman_Graham

If I understand correctly, you want to display the content of the DB one row at a time, possibly for up to 10,000 results. Shouldn't be a problem. There are a lot of code snippets on this forum that do just that. Here's one: http://www.phpbuilder.com/board/showthread.php?threadid=10266140

Basically, the code does what a search engine does - it retrieves as many results as you need at a time.

HTH

Norm

PS: I'll speak to my wife about that last bit :-)