sqlDelete

sqlDelete(table, [where])

table can be an in-memory table or a DFS table.

where (optional) is a metacode indicating the where condition.

Dynamically generate a metacode of the SQL delete statement. To execute the generated metacode, please use function eval.

Example 1. Delete the records in an in-memory table

t1=table(`A`B`C as symbol, 10 20 30 as x)
sqlDelete(t1, <symbol=`C>).eval()
t1;

Example 2. Delete the records in a DFS table

if(existsDatabase("dfs://db1")){
    dropDatabase("dfs://db1")
}

n=1000000
t=table(take(`A`B`C`D,n) as symbol, rand(10.0, n) as value)
db = database("dfs://db1", VALUE, `A`B`C`D)
Trades = db.createPartitionedTable(t, "Trades", "symbol")
Trades.append!(t)
select count(*) from Trades;

// output
1000000

Trades=loadTable("dfs://db1", "Trades")
sqlDelete(Trades, <symbol=`A>).eval()
select count(*) from Trades;

// output
750000