Pivot

Pivot

Manipulation of AST to handle PIVOT statement.

Constructor

new Pivot()

Source:

Methods

(static) addCalculatedPivotFieldsToAst(ast, pivotFieldData) → {Object}

Description:

  • Add new calculated fields to the existing SELECT fields. A field is add for each combination of aggregate function and unqiue pivot data points. The CASE function is used for each new field. A test is made if the column data equal the pivot data. If it is, the aggregate function data is returned, otherwise null. The GROUP BY is later applied and the appropiate pivot data will be calculated.

Source:
Parameters:
Name Type Description
ast Object

AST to be updated.
pivotFieldData Array.<Array.<any>>

Table data with unique pivot field data points.
Returns:
  • Abstract Sytax Tree with new SELECT fields with a CASE for each pivot data and aggregate function.
Type
Object

(static) getUniquePivotData(ast) → {Array.<Array.<any>>}

Description:

  • Find distinct pivot column data.

Source:
Parameters:
Name Type Description
ast Object

Abstract Syntax Tree containing the PIVOT option.
Returns:
  • All unique data points found in the PIVOT field for the given SELECT.
Type
Array.<Array.<any>>

(static) pivotField(ast, tables, bindData) → {Object}

Description:

  • Add new column to AST for every AGGREGATE function and unique pivot column data.

Source:
Parameters:
Name Type Description
ast Object

AST which is checked to see if a PIVOT is used.
tables Map.<String, Table>

Map of table info.
bindData BindData

List of bind data.
Returns:
  • Updated AST containing SELECT FIELDS for the pivot data OR original AST if no pivot.
Type
Object