blob

Syntax

blob(X)

Arguments

X is a string scalar/vector.

Details

Convert the data type of X to blob.

Examples

$ str="hello"
$ blob(str)
hello

$ t=table(1..10 as id, "A"+string(1..10) as sym, 2012.01.01..2012.01.10 as date, rand(100.0, 10) as val, rand(uuid(), 10) as uid)
$ str=toJson(t)
$ blob(str)

After a long string is converted to blob, it can be used as a column of an in-memory table:

$ d = dict(1..10000,  rand(1.0, 10000))
$ str=toStdJson(d);
$ t=table(blob(str) as jsonStr)

The blob type is also supported by the distributed table.

$ dbPath="dfs://testBlobDB"
$ if(existsDatabase(dbPath)){
$ dropDatabase(dbPath)
$ }
$ n=2000000
$ t=table(n:0,`date`id`type`num`blob,[DATETIME,INT,SYMBOL,DOUBLE,BLOB])
$ db1=database("",VALUE,2020.01.01..2020.01.10)
$ db2=database("",HASH,[INT,10])

$ db=database(dbPath,COMPO,[db1,db2])
$ pt1=createPartitionedTable(db,t,`pt1,`date`id)

$ date=concatDateTime(take(2020.01.01..2020.01.10,n),take(00:00:00..23:23:59,n))
$ id=rand(1..1000,n)
$ type=rand(`A`B`C`D`E,n)
$ num=rand(100.0,n)

$ blob=take(blob(string(1..10)),n)

$ t1=table(date,id,type,num,blob)
$ pt1.append!(t1)
$ select *  from pt1