setStreamTableFilterColumn

Syntax

setStreamTableFilterColumn(streamTable, columnName)

Arguments

streamTable is a stream table object.

columnName is a string indicating a column name. The column must be of type SYMBOL, STRING or INT.

Details

Specify the filtering column of a stream table. It is related to parameter filter in function subscribeTable The value of parameter filter is a vector. Only the rows with values of the filtering column in filter are published to the subscriber. A stream table can have only one filtering column.

Examples

In the following example, the filter column of the stream table “trades” is “symbol”. The table “trades_slave” on the same node subscribes to “trades” and the filter is set to [“IBM”, “GOOG”]. Only when the column “symbol” is “IBM” or “GOOG”, the corresponding data will be published.

$ share streamTable(10000:0,`time`symbol`price, [TIMESTAMP,SYMBOL,INT]) as trades
$ setStreamTableFilterColumn(trades, `symbol)
$ trades_1=table(10000:0,`time`symbol`price, [TIMESTAMP,SYMBOL,INT])

$ filter=symbol(`IBM`GOOG)

$ subscribeTable(tableName=`trades, actionName=`trades_1, handler=append!{trades_1}, msgAsTable=true, filter=filter);