savePartition

savePartition(dbHandle, table, tableName, [compression=true])

dbHandle is a DolphinDB database handle.

table is the table in memory to be saved.

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

compression (optional) 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 true.

Save a table as a partitioned DFS table. It must be executed by a logged-in user.

An empty table must be created with the function createPartitionedTable.

n=1000000
ID=rand(10, n)
value=rand(1.0, n)
t=table(ID, value);

db=database("dfs://rangedb_Trades", RANGE,  0 5 10)
Trades = db.createPartitionedTable(t, "Trades", "ID");
savePartition(db, t, `Trades)

Trades=loadTable(db, `Trades)
select count(value) from Trades;
// output
1,000,000

In the example above, the database db has two partitions: [0,5) and [5,10). Table t is saved as a partitioned table Trades with the partitioning column of ID in database db.

We can append another table to the table Trades:

n=500000
ID=rand(10, n)
value=rand(1.0, n)
t1=table(ID, value);
savePartition(db, t1, `Trades)
Trades=loadTable(db, `Trades)
select count(value) from Trades;
// output
1,500,000