Package com.snowflake.snowpark_java

Class Column

java.lang.Object

com.snowflake.snowpark_java.Column

Direct Known Subclasses:

CaseExpr

public class Column
extends Object

Represents a column or an expression in a DataFrame.

Since:

0.9.0

Method Summary

Modifier and Type	Method	Description
Column	alias(String alias)	Retrieves s new renamed Column.
Column	and(Column other)	And.
Column	as(String alias)	Retrieves s new renamed Column.
Column	asc()	Sorts this column in ascending order.
Column	asc_nulls_first()	Sorts this column in ascending order, null values sorted before non-null values.
Column	asc_nulls_last()	Sorts this column in ascending order, null values sorted after non-null values.
Column	between(Column lowerBound, Column upperBound)	Between lower bound (including) and upper bound (including).
Column	bitand(Column other)	Bitwise and.
Column	bitor(Column other)	Bitwise or.
Column	bitxor(Column other)	Bitwise xor.
Column	cast(DataType to)	Casts the values in the Column to the specified data type.
Column	collate(String collateSpec)	Returns a copy of the original Column with the specified 'collateSpec` property, rather than the original collation specification property.
Column	desc()	Sorts this column in descending order.
Column	desc_nulls_first()	Sorts this column in descending order, null values sorted before non-null values.
Column	desc_nulls_last()	Sorts this column in descending order, null values sorted after non-null values.
Column	divide(Column other)	Divide
Column	equal_nan()	Is NaN.
Column	equal_null(Column other)	Equal to.
Column	equal_to(Column other)	Equal to.
Column	geq(Column other)	Greater than or equal to.
Optional<String>	getName()	Retrieves the column name (if the column has a name).
Column	gt(Column other)	Greater than.
Column	in(DataFrame df)	Returns a conditional expression that you can pass to the filter or where method to perform a WHERE ...
Column	in(Object... values)	Returns a conditional expression that you can pass to the filter or where method to perform the equivalent of a WHERE ...
Column	is_not_null()	Is not null.
Column	is_null()	Is null.
Column	leq(Column other)	Less than or equal to.
Column	like(Column pattern)	Allows case-sensitive matching of strings based on comparison with a pattern.
Column	lt(Column other)	Less than.
Column	minus(Column other)	Minus
Column	mod(Column other)	Remainder
Column	multiply(Column other)	Multiply
Column	not_equal(Column other)	Not equal to.
Column	or(Column other)	Or.
Column	over()	Returns a windows frame, based on the specified WindowSpec.
Column	over(WindowSpec windowSpec)	Returns a windows frame, based on the specified WindowSpec.
Column	plus(Column other)	Plus
Column	regexp(Column pattern)	Returns true if this column matches the specified regular expression.
Column	subField(int index)	Retrieves the element (field) at the specified index in a column that contains semi-structured data.
Column	subField(String field)	Retrieves the specified element (field) in a column that contains semi-structured data.
String	toString()	Retrieves a string representation of the expression corresponding to this Column instance.
Column	unary_minus()	Unary minus.
Column	unary_not()	Unary not.
Column	withinGroup(Column... cols)	Returns a Column expression that adds a WITHIN GROUP clause to sort the rows by the specified sequence of columns.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

subField

public Column subField(String field)

Retrieves the specified element (field) in a column that contains semi-structured data.

The method applies case-sensitive matching to the names of the specified elements.

This is equivalent to using bracket notation in SQL (`column['element']`).

If the column is an OBJECT value, this function extracts the VARIANT value of the element with the specified name from the OBJECT value. If the element is not found, the method returns NULL. You must not specify an empty string for the element name.

If the column is a VARIANT value, this function first checks if the VARIANT value contains an OBJECT value. If the VARIANT value does not contain an OBJECT value, the method returns NULL. Otherwise, the method works as described above.

For example:

 df.select(df.col("src").subField("salesperson").subField("emails").subField(0))
 

Parameters:

field - The field name of the subfield to be extracted. You cannot specify a path.

Returns:

The sub-field of this column

Since:

0.9.0

subField

public Column subField(int index)

Retrieves the element (field) at the specified index in a column that contains semi-structured data.

The method applies case-sensitive matching to the names of the specified elements.

This is equivalent to using bracket notation in SQL (`column['element']`).

If the column is an ARRAY value, this function extracts the VARIANT value of the ARRAY element at the specified index. If the index points outside of the array boundaries or if an element does not exists at the specified index (e.g. if the array is sparsely populated), the method returns NULL.

If the column is a VARIANT value, this functions first checks if the VARIANT value contains an ARRAY value. If the VARIANT value does not contain an ARRAY value, the method returns NULL. Otherwise, the method works as described above.

 df.select(df.col("src").subField(1).subField(0))
 

Parameters:

index - The index of the subfield to be extracted

Returns:

The sub-field of this column

Since:

0.9.0

getName

public Optional<String> getName()

Retrieves the column name (if the column has a name).

Returns:

An Optional String

Since:

0.9.0

as

public Column as(String alias)

Retrieves s new renamed Column.

Parameters:

alias - The new column name

Returns:

A new Column object

Since:

0.9.0

alias

public Column alias(String alias)

Retrieves s new renamed Column.

Parameters:

alias - The new column name

Returns:

A new Column object

Since:

0.9.0

unary_minus

public Column unary_minus()

Unary minus.

Returns:

The result column object

Since:

0.9.0

unary_not

public Column unary_not()

Unary not.

Returns:

The result column object

Since:

0.9.0

equal_to

public Column equal_to(Column other)

Equal to.

Parameters:

other - The column being compared

Returns:

The result column object

Since:

0.9.0

not_equal

public Column not_equal(Column other)

Not equal to.

Parameters:

other - The column being compared

Returns:

The result column object

Since:

0.9.0

gt

public Column gt(Column other)

Greater than.

Parameters:

other - The column being compared

Returns:

The result column object

Since:

0.9.0

lt

public Column lt(Column other)

Less than.

Parameters:

other - The column being compared

Returns:

The result column object

Since:

0.9.0

leq

public Column leq(Column other)

Less than or equal to.

Parameters:

other - The column being compared

Returns:

The result column object

Since:

0.9.0

geq

public Column geq(Column other)

Greater than or equal to.

Parameters:

other - The column being compared

Returns:

The result column object

Since:

0.9.0

equal_null

public Column equal_null(Column other)

Equal to. This function can be used to compare against a null value.

Parameters:

other - The column being compared

Returns:

The result column object

Since:

0.9.0

equal_nan

public Column equal_nan()

Is NaN.

Returns:

The result column object

Since:

0.9.0

is_null

public Column is_null()

Is null.

Returns:

The result column object

Since:

0.9.0

is_not_null

public Column is_not_null()

Is not null.

Returns:

The result column object

Since:

0.9.0

or

public Column or(Column other)

Or.

Parameters:

other - The other column

Returns:

The result column object

Since:

0.9.0

and

public Column and(Column other)

And.

Parameters:

other - The other column

Returns:

The result column object

Since:

0.9.0

between

public Column between(Column lowerBound,
                      Column upperBound)

Between lower bound (including) and upper bound (including).

Parameters:

lowerBound - the lower bound

upperBound - the upper bound

Returns:

The result column object

Since:

0.9.0

plus

public Column plus(Column other)

Plus

Parameters:

other - The column being added

Returns:

The result column object

Since:

0.9.0

minus

public Column minus(Column other)

Minus

Parameters:

other - The column being subtracted

Returns:

The result column object

Since:

0.9.0

multiply

public Column multiply(Column other)

Multiply

Parameters:

other - The column being multiplied

Returns:

The result column object

Since:

0.9.0

divide

public Column divide(Column other)

Divide

Parameters:

other - The column being divided

Returns:

The result column object

Since:

0.9.0

mod

public Column mod(Column other)

Remainder

Parameters:

other - The column being calculated

Returns:

The result column object

Since:

0.9.0

cast

public Column cast(DataType to)

Casts the values in the Column to the specified data type.

Parameters:

to - The target data type

Returns:

The result column object

Since:

0.9.0

desc

public Column desc()

Sorts this column in descending order.

Returns:

The result column object

Since:

0.9.0

desc_nulls_first

public Column desc_nulls_first()

Sorts this column in descending order, null values sorted before non-null values.

Returns:

The result column object

Since:

0.9.0

desc_nulls_last

public Column desc_nulls_last()

Sorts this column in descending order, null values sorted after non-null values.

Returns:

The result column object

Since:

0.9.0

asc

public Column asc()

Sorts this column in ascending order.

Returns:

The result column object

Since:

0.9.0

asc_nulls_first

public Column asc_nulls_first()

Sorts this column in ascending order, null values sorted before non-null values.

Returns:

The result column object

Since:

0.9.0

asc_nulls_last

public Column asc_nulls_last()

Sorts this column in ascending order, null values sorted after non-null values.

Returns:

The result column object

Since:

0.9.0

bitor

public Column bitor(Column other)

Bitwise or.

Parameters:

other - The column being calculated

Returns:

The result column object

Since:

0.9.0

bitand

public Column bitand(Column other)

Bitwise and.

Parameters:

other - The column being calculated

Returns:

The result column object

Since:

0.9.0

bitxor

public Column bitxor(Column other)

Bitwise xor.

Parameters:

other - The column being calculated

Returns:

The result column object

Since:

0.9.0

like

public Column like(Column pattern)

Allows case-sensitive matching of strings based on comparison with a pattern.

For details, see the Snowflake documentation on regular expressions

Parameters:

pattern - A regular expression

Returns:

The result column object

Since:

0.9.0

regexp

public Column regexp(Column pattern)

Returns true if this column matches the specified regular expression.

For details, see the Snowflake documentation on regular expressions

Parameters:

pattern - A regular expression

Returns:

The result column object

Since:

0.9.0

collate

public Column collate(String collateSpec)

Returns a copy of the original Column with the specified 'collateSpec` property, rather than the original collation specification property.

For details, see the Snowflake documentation on collation specifications

Parameters:

collateSpec - The collation specification

Returns:

The result column object

Since:

0.9.0

over

public Column over()

Returns a windows frame, based on the specified WindowSpec.

Returns:

The result column object

Since:

0.9.0

See Also:

WindowSpec

over

public Column over(WindowSpec windowSpec)

Returns a windows frame, based on the specified WindowSpec.

Parameters:

windowSpec - The window frame specification

Returns:

The result column object

Since:

0.1.0

withinGroup

public Column withinGroup(Column... cols)

Returns a Column expression that adds a WITHIN GROUP clause to sort the rows by the specified sequence of columns.

This method is supported on Column expressions returned by some aggregate functions, including functions.array_agg, LISTAGG(), PERCENTILE_CONT(), and PERCENTILE_DISC().

For example:

 df.groupBy(df.col("col1")).agg(Functions.listagg(df.col("col2"), ",")
      .withinGroup(df.col("col2").asc()))
 

Parameters:

cols - A list of Columns

Returns:

The result Column

Since:

1.1.0

in

public Column in(Object... values)

Returns a conditional expression that you can pass to the filter or where method to perform the equivalent of a WHERE ... IN query with a specified list of values.

The expression evaluates to true if the value in the column is one of the values in a specified sequence.

For example, the following code returns a DataFrame that contains the rows where the column "a" contains the value 1, 2, or 3. This is equivalent to SELECT * FROM table WHERE a IN (1, 2, 3).

 df.filter(df.col("a").in(1, 2, 3))
 

Parameters:

values - The value list

Returns:

The result Column

Since:

1.2.0

in

public Column in(DataFrame df)

Returns a conditional expression that you can pass to the filter or where method to perform a WHERE ... IN query with a specified subquery.

The expression evaluates to true if the value in the column is one of the values in the column of the same name in a specified DataFrame.

For example, the following code returns a DataFrame that contains the rows where the column "a" of `df2` contains one of the values from column "a" in `df1`. This is equivalent to SELECT * FROM table2 WHERE a IN (SELECT a FROM table1).

 DataFrame df1 = session.table(table1);
 DataFrame df2 = session.table(table2);
 df2.filter(df1.col("a").in(df1));
 

Parameters:

df - A DataFrame contains target values

Returns:

The return column.

Since:

1.2.0

toString

public String toString()

Retrieves a string representation of the expression corresponding to this Column instance.

Overrides:

toString in class Object

Returns:

A String representing this expression

Since:

0.9.0