Package io.delta.kernel.expressions

Class ScalarExpression

Object
io.delta.kernel.expressions.ScalarExpression
All Implemented Interfaces:
Expression
Direct Known Subclasses:
Predicate
@Evolving public class ScalarExpression extends Object implements Expression
Scalar SQL expressions which take zero or more inputs and for each input row generate one output value. A subclass of these expressions are of type Predicate whose result type is `boolean`. See Predicate for predicate type scalar expressions. Supported non-predicate type scalar expressions are listed below.
  1. Name: element_at
    • Semantic: element_at(map, key). Return the value of given key from the map type input. Returns null if the given key is not in the map Ex: `element_at(map(1, 'a', 2, 'b'), 2)` returns 'b'
    • Since version: 3.0.0
  2. Name: COALESCE
    • Semantic: COALESCE(expr1, ..., exprN) Return the first non-null argument. If all arguments are null returns null
    • Since version: 3.1.0
  3. Name: TIMEADD
    • Semantic: TIMEADD(colExpr, milliseconds). Add the specified number of milliseconds to the timestamp represented by colExpr. The adjustment does not alter the original value but returns a new timestamp increased by the given milliseconds. Ex: `TIMEADD(timestampColumn, 1000)` returns a timestamp 1 second later.
    • Since version: 3.3.0
  4. Name: SUBSTRING
    • Semantic: SUBSTRING(colExpr, pos, len). Returns the slice of byte array or string, that starts at pos and has the length len.
      • pos is 1 based. If pos is negative the start is determined by counting characters (or bytes for BINARY) from the end.
      • If len is less than 1 the result is empty.
      • If len is omitted the function returns on characters or bytes starting with pos.
    • Since version: 3.4.0
Since:
3.0.0