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existsDatabase

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existsDatabase

Syntax

existsDatabase(dbUrl)

Details

Check if a database exists under the specified folder.

Parameters

dbUrl is a string indicating the path of a database folder.

Returns

A Boolean scalar. true and false represent the specified database exists/does not exist, respectively.

Examples

To check if a DFS database exists:

n=1000000
ID=rand(10, n)
dates=2017.08.07..2017.08.11
date=rand(dates, n)
x=rand(10.0, n)
t=table(ID, date, x)

db = database("dfs://valueDB", VALUE, 2017.08.07..2017.08.11)
pt = db.createPartitionedTable(t, `pt, `date);
pt.append!(t);

existsDatabase("dfs://valueDB");
// output: true

existsDatabase("dfs://valueDB/20170807");
// output: false