Question : Question regarding varchar index and limit in MySQL and MS SQL

Hi,

I am reading a varchar field (call it vfield) from MySQL into MS SQL using openquery function. The mysql field is type varchar and is the primary key. There are 2 million of these mysql rows that I would need to read into mssql environment. Trouble is odbc can't handle the entire read in 1 transaction so I would have to do this piecemeal, maybe about 100k rows at a time. Trouble is how do I keep track of the maximum of vfield during each read so that i can go and fetch the next 100k rows on the next read, and so on until the entire table is read?

Is there a syntax that can give me the vfield on 100k row so i can keep track of this value for next read? I couldn't figure out how to do this w/ the limit clause. Maybe MySQL has another fcn for this? Thx.

Answer : Question regarding varchar index and limit in MySQL and MS SQL

the LIMIT is the way to go:

                       
         
           
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             first read: 
SELECT * 
FROM yourtable 
ORDER BY vField
LIMIT 0,10000 
second read: 
first read: 
SELECT * 
FROM yourtable 
ORDER BY vField
LIMIT 10000,10000 

third read: 
SELECT * 
FROM yourtable 
ORDER BY vField
LIMIT 20000,10000 
etc.

           
         

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