Cassandra: Update multiple rows?
In mysql, I can do the following query, UPDATE mytable SET price = '100' WHERE manuf开发者_开发技巧acturer='22'
Can this be done with cassandra?
Thanks!
For that you will need to maintain your own index in a separate column family (you need a way to find all products (product ids) that are manufactured by a certatin manufacturer. When you have all the product ids doing a batch mutation is simple). E.g
ManufacturerToProducts = { // this is a ColumnFamily
'22': { // this is the key to this Row inside the CF
// now we have an infinite # of columns in this row
'prod_1': "prod_1", //for simplicity I'm only showing the value (but in reality the values in the map are the entire Column.)
'prod_1911' : null
}, // end row
'23': { // this is the key to another row in the CF
// now we have another infinite # of columns in this row
'prod_1492': null,
},
}
(disclaimer: thanks Arin for the annotation used above)
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