예제 #1
0
  public String convertToPostgres(Expression transformationFunctionExpression, boolean withRel) {

    String functionExpression =
        transformationFunctionExpression.getJepExpression().toStringForSql();
    // first fix attribute names
    for (VariablePathExpression vpe : transformationFunctionExpression.getAttributePaths()) {
      if (functionExpression.contains(vpe.toString())) {
        String expressionToCheckForSigns =
            transformationFunctionExpression.getJepExpression().toString();
        int startIndex = expressionToCheckForSigns.indexOf(vpe.toString());
        int endIndex = startIndex + vpe.toString().length();
        boolean castToFloat = false;
        // check so that the String index will not get out of bounds
        if (startIndex - 2 >= 0) {
          if (math_sign.contains(expressionToCheckForSigns.charAt(startIndex - 2))) {
            castToFloat = true;
          }
          // to catch the '>=' or '<=' case
          else if (expressionToCheckForSigns.charAt(startIndex - 2) == '=' && startIndex - 3 >= 0) {
            if (expressionToCheckForSigns.charAt(startIndex - 3) == '<'
                || expressionToCheckForSigns.charAt(startIndex - 3) == '>') {
              castToFloat = true;
            }
          }
        }
        if (endIndex + 2 <= expressionToCheckForSigns.length()) {
          if (math_sign.contains(expressionToCheckForSigns.charAt(endIndex + 1))) {
            castToFloat = true;
          }
        }
        String newAttrName;
        // replace them with the corresponding attribute name
        if (withRel) {
          newAttrName = GenerateSQL.attributeNameWithVariable(vpe);
        } else {
          newAttrName = GenerateSQL.attributeNameInVariable(vpe);
        }
        // if previous or next character is one of {+,-,*,/,<,>} cast it to float
        if (castToFloat) {
          functionExpression =
              functionExpression.replaceAll(vpe.toString(), "cast(" + newAttrName + " as float)");
        } else {
          functionExpression = functionExpression.replaceAll(vpe.toString(), newAttrName);
        }
      }
    }
    return replaceExpression(functionExpression);
  }
예제 #2
0
 private static String sqlString(Expression expression) {
   String result = "";
   List<VariablePathExpression> attributePaths = expression.getAttributePaths();
   if (expression.toString().startsWith("isNull(")) {
     String attributeName = extractAttributeNameFromExpression(attributePaths.get(0));
     return attributeName + " IS NULL";
   }
   if (expression.toString().startsWith("isNotNull(")) {
     String attributeName = extractAttributeNameFromExpression(attributePaths.get(0));
     return attributeName + " IS NOT NULL";
   }
   for (VariablePathExpression attributePath : attributePaths) {
     String attributeName = extractAttributeNameFromExpression(attributePaths.get(0));
     result = expression.toString().replaceAll(attributePath.toString(), attributeName);
   }
   result = result.replaceAll("==", "=");
   result = result.replaceAll("\"", "\'");
   return result.replaceAll("&&", "AND");
 }