Class ColumnExpression

This is a handle to a column expression. This class is created by the factory methods Create(expression), and can be used to retrieve information about the components of the column expression.

Since

2.0

Hierarchy (view full)

Methods

Cast Equals GetHashCode ToString TryCast Equals

Default capability

Alias ColumnNames ErrorDisplayMessage ErrorExpression ErrorMessage Expression HierarchyNames IsValid MethodNames Clone ContainsAggregationMethod GetExpressionReturnType QualifyNames RenameColumn RenameHierarchy Validate Create CreateFromPlotExpression

Methods

Cast

  • Cast<T1, T2>(this, type): T1

  • Casts this object to the specified type. Throws error on failure.

    Type Parameters

    • T1

      The target type of the cast.

    • T2

      The type of the object to cast.

    Parameters

    Returns T1

Equals

  • Equals(obj): boolean

  • Determines whether the specified object is equal to the current object.

    Parameters

    • obj: any

      The object to compare with the current object.

    Returns boolean

    true if the specified object is equal to the current object; otherwise, false.

GetHashCode

  • GetHashCode(): number

  • Serves as the default hash function.

    Returns number

    A hash code for the current object.

ToString

  • ToString(): string

  • Returns a string that represents the current object.

    Returns string

    A string that represents the current object.

TryCast

  • TryCast<T1, T2>(this, type): null | T1

  • Casts this object to the specified type. Returns null on failure.

    Type Parameters

    • T1

      The target type of the cast.

    • T2

      The type of the object to cast.

    Parameters

    Returns null | T1

StaticEquals

  • Equals(objA, objB): boolean

  • Determines whether the specified object instances are considered equal.

    Parameters

    • objA: any

      The first object to compare.

    • objB: any

      The second object to compare.

    Returns boolean

    true if the objects are considered equal; otherwise, false. If both objA and objB are null, the method returns true.

Default capability

Alias

  • get Alias(): string

  • Get the alias (name) of the calculated column if there is an AS part of the column expression.

    Returns string

    Since

    2.0

ColumnNames

ErrorDisplayMessage

  • get ErrorDisplayMessage(): string

  • Get the localized error message if the expression is invalid, null otherwise.

    Returns string

    Since

    2.0

ErrorExpression

  • get ErrorExpression(): string

  • Get the expression that could not be parsed if it exists, if the expression is valid then this property is null.

    Returns string

    Since

    2.0

ErrorMessage

  • get ErrorMessage(): string

  • Get the error message if the expression is invalid, null otherwise.

    Returns string

    Since

    2.0

Expression

  • get Expression(): string

  • Gets the expression as a string. This would exclude any alias (name) statement.

    Returns string

    Since

    2.0

HierarchyNames

IsValid

  • get IsValid(): boolean

  • True if the expression is valid, false otherwise.

    Returns boolean

    Since

    2.0

MethodNames

Clone

ContainsAggregationMethod

  • ContainsAggregationMethod(table): boolean

  • Checks if column expression contains an aggregation method.

    Parameters

    Returns boolean

    True if the column expression contained an aggregation method, false otherwise.

    Since

    2.0

GetExpressionReturnType

  • GetExpressionReturnType(table): DataType

  • Get the result type for the given expression using the columns in the specified table.

    Parameters

    Returns DataType

    The return type of the expression.

    Since

    2.0

QualifyNames

  • QualifyNames(tableName): void

  • Make sure that all column/hierarchy references in the query are fully qualified.

    Parameters

    • tableName: string | String

      The table name.

    Returns void

    Since

    2.0

RenameColumn

  • RenameColumn(oldName, newName): void

  • Rename all column references from oldName to newName.

    Parameters

    • oldName: string | String

      The old column name.

    • newName: string | String

      The new column name.

    Returns void

    Since

    2.0

RenameHierarchy

  • RenameHierarchy(oldName, newName): void

  • Rename all hierarchy references from oldName to newName.

    Parameters

    • oldName: string | String

      The old hierarchy name.

    • newName: string | String

      The new hierarchy name.

    Returns void

    Since

    2.0

Validate

  • Validate(table): boolean

  • Validates if the column expression is valid in the given Spotfire.Dxp.Data.DataTable context.

    Parameters

    Returns boolean

    True if the expression is valid, false otherwise.

    Since

    2.0

StaticCreate

  • Create(expression): ColumnExpression

  • Parse a column expression and return a ColumnExpression.

    Parameters

    • expression: string | String

      The column expression.

    Returns ColumnExpression

    A handle to the parsed column expression. Even if it was not possible to parse the expression a ColumnExpression will still be returned but it will be invalid.

    Since

    2.0

StaticCreateFromPlotExpression

Settings

Member Visibility

On This Page

Methods
Default capability