public static String projectionOnTargetValuesFromCorrespondences(
List<VariableCorrespondence> correspondences, String fromClause, String whereClause) {
StringBuilder result = new StringBuilder();
result.append(INDENT).append("select distinct \n");
for (int i = 0; i < correspondences.size(); i++) {
VariableCorrespondence correspondence = correspondences.get(i);
if (correspondence.getSourcePaths() != null) {
result
.append(DOUBLE_INDENT)
.append(GenerateSQL.attributeNameWithVariable(correspondence.getFirstSourcePath()));
} else {
String sourcePathName = correspondence.getSourceValue().toString();
sourcePathName = sourcePathName.replaceAll("\"", "\'");
result.append(DOUBLE_INDENT).append(sourcePathName);
}
result
.append(" as ")
.append(GenerateSQL.attributeNameInVariable(correspondence.getFirstSourcePath()));
if (i != correspondences.size() - 1) result.append(",\n");
}
result.append("\n");
result.append(INDENT).append(fromClause);
if (!whereClause.equals("")) {
result.append(INDENT).append(whereClause);
}
return result.toString();
}
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);
}