/** Converts an expression from {@link RexNode} to {@link SqlNode} format. */
SqlNode toSql(RexProgram program, RexNode rex) {
if (rex instanceof RexLocalRef) {
final int index = ((RexLocalRef) rex).getIndex();
return toSql(program, program.getExprList().get(index));
} else if (rex instanceof RexInputRef) {
return field(((RexInputRef) rex).getIndex());
} else if (rex instanceof RexLiteral) {
final RexLiteral literal = (RexLiteral) rex;
switch (literal.getTypeName().getFamily()) {
case CHARACTER:
return SqlLiteral.createCharString((String) literal.getValue2(), POS);
case NUMERIC:
case EXACT_NUMERIC:
return SqlLiteral.createExactNumeric(literal.getValue().toString(), POS);
case APPROXIMATE_NUMERIC:
return SqlLiteral.createApproxNumeric(literal.getValue().toString(), POS);
case BOOLEAN:
return SqlLiteral.createBoolean((Boolean) literal.getValue(), POS);
case DATE:
return SqlLiteral.createDate((Calendar) literal.getValue(), POS);
case TIME:
return SqlLiteral.createTime(
(Calendar) literal.getValue(), literal.getType().getPrecision(), POS);
case TIMESTAMP:
return SqlLiteral.createTimestamp(
(Calendar) literal.getValue(), literal.getType().getPrecision(), POS);
case ANY:
switch (literal.getTypeName()) {
case NULL:
return SqlLiteral.createNull(POS);
// fall through
}
default:
throw new AssertionError(literal + ": " + literal.getTypeName());
}
} else if (rex instanceof RexCall) {
final RexCall call = (RexCall) rex;
final SqlOperator op = call.getOperator();
final List<SqlNode> nodeList = toSql(program, call.getOperands());
if (op == SqlStdOperatorTable.CAST) {
RelDataType type = call.getType();
if (type.getSqlTypeName() == SqlTypeName.VARCHAR
&& dialect.getDatabaseProduct() == SqlDialect.DatabaseProduct.MYSQL) {
// MySQL doesn't have a VARCHAR type, only CHAR.
nodeList.add(
new SqlDataTypeSpec(
new SqlIdentifier("CHAR", POS), type.getPrecision(), -1, null, null, POS));
} else {
nodeList.add(toSql(type));
}
}
if (op == SqlStdOperatorTable.CASE) {
final SqlNode valueNode;
final List<SqlNode> whenList = Expressions.list();
final List<SqlNode> thenList = Expressions.list();
final SqlNode elseNode;
if (nodeList.size() % 2 == 0) {
// switched:
// "case x when v1 then t1 when v2 then t2 ... else e end"
valueNode = nodeList.get(0);
for (int i = 1; i < nodeList.size() - 1; i += 2) {
whenList.add(nodeList.get(i));
thenList.add(nodeList.get(i + 1));
}
} else {
// other: "case when w1 then t1 when w2 then t2 ... else e end"
valueNode = null;
for (int i = 0; i < nodeList.size() - 1; i += 2) {
whenList.add(nodeList.get(i));
thenList.add(nodeList.get(i + 1));
}
}
elseNode = nodeList.get(nodeList.size() - 1);
return op.createCall(
POS,
valueNode,
new SqlNodeList(whenList, POS),
new SqlNodeList(thenList, POS),
elseNode);
}
if (op instanceof SqlBinaryOperator && nodeList.size() > 2) {
// In RexNode trees, OR and AND have any number of children;
// SqlCall requires exactly 2. So, convert to a left-deep binary tree.
return createLeftCall(op, nodeList);
}
return op.createCall(new SqlNodeList(nodeList, POS));
} else {
throw new AssertionError(rex);
}
}
public SqlNode visit(SqlLiteral literal) {
return (SqlNode) literal.clone();
}
public int reduceExpr(int opOrdinal, List<Object> list) {
final SqlParserUtil.ToTreeListItem betweenNode =
(SqlParserUtil.ToTreeListItem) list.get(opOrdinal);
SqlOperator op = betweenNode.getOperator();
assert op == this;
// Break the expression up into expressions. For example, a simple
// expression breaks down as follows:
//
// opOrdinal endExp1
// | |
// a + b BETWEEN c + d AND e + f
// |_____| |_____| |_____|
// exp0 exp1 exp2
// Create the expression between 'BETWEEN' and 'AND'.
final SqlParserPos pos = ((SqlNode) list.get(opOrdinal + 1)).getParserPosition();
SqlNode exp1 = SqlParserUtil.toTreeEx(list, opOrdinal + 1, 0, SqlKind.AND);
if ((opOrdinal + 2) >= list.size()) {
SqlParserPos lastPos = ((SqlNode) list.get(list.size() - 1)).getParserPosition();
final int line = lastPos.getEndLineNum();
final int col = lastPos.getEndColumnNum() + 1;
SqlParserPos errPos = new SqlParserPos(line, col, line, col);
throw SqlUtil.newContextException(
errPos, EigenbaseResource.instance().BetweenWithoutAnd.ex());
}
final Object o = list.get(opOrdinal + 2);
if (!(o instanceof SqlParserUtil.ToTreeListItem)) {
SqlParserPos errPos = ((SqlNode) o).getParserPosition();
throw SqlUtil.newContextException(
errPos, EigenbaseResource.instance().BetweenWithoutAnd.ex());
}
if (((SqlParserUtil.ToTreeListItem) o).getOperator().getKind() != SqlKind.AND) {
SqlParserPos errPos = ((SqlParserUtil.ToTreeListItem) o).getPos();
throw SqlUtil.newContextException(
errPos, EigenbaseResource.instance().BetweenWithoutAnd.ex());
}
// Create the expression after 'AND', but stopping if we encounter an
// operator of lower precedence.
//
// For example,
// a BETWEEN b AND c + d OR e
// becomes
// (a BETWEEN b AND c + d) OR e
// because OR has lower precedence than BETWEEN.
SqlNode exp2 = SqlParserUtil.toTreeEx(list, opOrdinal + 3, getRightPrec(), SqlKind.OTHER);
// Create the call.
SqlNode exp0 = (SqlNode) list.get(opOrdinal - 1);
SqlCall newExp =
createCall(
betweenNode.getPos(),
exp0,
exp1,
exp2,
SqlLiteral.createSymbol(flag, SqlParserPos.ZERO));
// Replace all of the matched nodes with the single reduced node.
SqlParserUtil.replaceSublist(list, opOrdinal - 1, opOrdinal + 4, newExp);
// Return the ordinal of the new current node.
return opOrdinal - 1;
}