Package org.apache.empire.db.expr.column


package org.apache.empire.db.expr.column
This package contains SQL-generator classes for column expressions. There is no need to use these classes directly. They are internally created through functions on the DBColumnExpr object.
  • Class
    Description
    This implements some basic functionality for SQL functions based on a column expression
    This class allows column renaming in SQL.
    This class is used for performing calculations in SQL
    It handles the mathematical operations ("+", "-", "*", "/") for the current column.
    This class represents a SQL case expression like "case when ?
    This class is used to create a SQL CASE constraint in the form of case {expr} when {value1} then {result1} when {value2} then {result2} ...
    This class is used to create a SQL CASE constraint in the form of case when {cond1} then {result1} when {cond2} then {result2} ...
     
     
    This class is used for performing string concatenation in SQL
    DBConcatExpression
    This class is used to convert a value to a different data type.
    This class is used to add the "count" statement to the SQL-Command.
    This class is used to decode a set of keys to the corresponding target values.
    This class is used for performing various SQL functions on a column or column expression.
    This class allows column renaming in SQL.
    DBPreparable This interface indicates that a DBExpr Object wants to perform preparation tasks when added to a DBCommand
    This class is used for declaring scalar functions in SQL (like e.g. random).
    This class is used for declaring constant values in SQL.