saveDualPartition

Syntax

saveDualPartition(dbHandle1, dbHandle2, table, tableName, partitionColumn1, partitionColumn2, [compression=false])

Arguments

dbHandle1 is the database handle of the first level partition.

dbHandle2 is the database handle of the second level partition.

table is the table in memory to be saved.

tableName is a string indicating the desired name of the saved partitioned table.

partitionColumn1 is a string indicating the partitioning column of the first level partition.

partitionColumn2 is a string indicating the partitioning column of the second level partition.

compression is a Boolean variable. It sets the compression mode. When it is set to true, the table will be saved to disk in compression mode. The default value is false.

Details

Save a table in the local node before sharing it to other nodes to form a dual partition database. It must be executed by a logged-in user.

It is used together with statement share. If the partition and a table already exist, the function will append the new data to the existing table.

Examples

$ n=1000000
$ ID=rand(10, n)
$ dates=2017.08.07..2017.08.11
$ date=rand(dates, n)
$ x=rand(1.0, n)
$ t=table(ID, date, x);

$ hdb = database("C:/DolphinDB/Data/dualDB", RANGE,  0 5 10)
$ vdb = database(, VALUE, dates)
$ saveDualPartition(hdb, vdb, t, `tDualPartition, `ID, `date)