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work on order by began

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VaclavT
2021-07-28 22:29:05 +02:00
parent 7d91319f0b
commit 34e432d031
10 changed files with 184 additions and 92 deletions
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83
parser.cpp
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@@ -176,7 +176,7 @@ namespace usql {
return std::make_unique<InsertIntoTableNode>(table_name, column_names, std::move(column_values));
}
std::unique_ptr<Node> Parser::parse_value() {
std::unique_ptr<Node> Parser::parse_value() {
if (m_lexer.tokenType() == TokenType::int_number) {
return std::make_unique<IntValueNode>(std::stoi(m_lexer.consumeCurrentToken().token_string));
}
@@ -205,9 +205,9 @@ std::unique_ptr<Node> Parser::parse_value() {
}
throw Exception("Syntax error, current token: " + m_lexer.currentToken().token_string);
}
}
std::unique_ptr<Node> Parser::parse_select_from_table() {
std::unique_ptr<Node> Parser::parse_select_from_table() {
auto cols = std::make_unique<std::vector<SelectColNode>>();
m_lexer.skipToken(TokenType::keyword_select);
@@ -235,12 +235,13 @@ std::unique_ptr<Node> Parser::parse_select_from_table() {
std::unique_ptr<Node> where_node = parse_where_clause();
// if (m_lexer.tokenType() == TokenType::keyword_order_by) {}
std::vector<ColOrderNode> orderby_node = parse_orderby_clause();
// if (m_lexer.tokenType() == TokenType::keyword_offset) {}
// if (m_lexer.tokenType() == TokenType::keyword_limit) {}
return std::make_unique<SelectFromTableNode>(table_name, std::move(cols), std::move(where_node));
}
return std::make_unique<SelectFromTableNode>(table_name, std::move(cols), std::move(where_node), orderby_node);
}
std::unique_ptr<Node> Parser::parse_delete_from_table() {
m_lexer.skipToken(TokenType::keyword_delete);
@@ -291,26 +292,62 @@ std::unique_ptr<Node> Parser::parse_select_from_table() {
}
std::unique_ptr<Node> Parser::parse_where_clause() {
// TODO add support for multiple filters
// TODO add support for parenthesis
if (m_lexer.tokenType() != TokenType::keyword_where) {
return std::make_unique<TrueNode>();
}
if (m_lexer.tokenType() != TokenType::keyword_where) {
return std::make_unique<TrueNode>();
}
std::unique_ptr<Node> node;
m_lexer.skipToken(TokenType::keyword_where);
do {
node = parse_relational_expression();
std::unique_ptr<Node> node;
m_lexer.skipToken(TokenType::keyword_where);
do {
node = parse_relational_expression();
if (Lexer::isLogicalOperator(m_lexer.tokenType())) {
auto operation = parse_logical_operator();
std::unique_ptr<Node> node2 = parse_relational_expression();
node = std::make_unique<LogicalOperatorNode>(operation, std::move(node), std::move(node2));
}
} while (m_lexer.tokenType() != TokenType::eof && m_lexer.tokenType() != TokenType::keyword_order);
if (Lexer::isLogicalOperator(m_lexer.tokenType())) {
auto operation = parse_logical_operator();
std::unique_ptr<Node> node2 = parse_relational_expression();
node = std::make_unique<LogicalOperatorNode>(operation, std::move(node), std::move(node2));
}
} while (m_lexer.tokenType() != TokenType::eof); // until whole where clause parsed
return node;
}
return node;
std::vector<ColOrderNode> Parser::parse_orderby_clause() {
std::vector<ColOrderNode> order_cols;
if (m_lexer.tokenType() == TokenType::keyword_order) {
m_lexer.skipToken(TokenType::keyword_order);
m_lexer.skipToken(TokenType::keyword_by);
do {
int col_index = -1;
bool asc = true;
auto token_type = m_lexer.tokenType();
std::string tokenString = m_lexer.consumeCurrentToken().token_string;
switch (token_type) {
case TokenType::int_number:
col_index = std::stoi(tokenString);
break;
default:
throw Exception("column index alloved in order by clause at this moment");
}
if (m_lexer.tokenType() == TokenType::keyword_asc) {
m_lexer.skipToken(TokenType::keyword_asc);
} else if (m_lexer.tokenType() == TokenType::keyword_desc) {
m_lexer.skipToken(TokenType::keyword_desc);
asc = false;
}
order_cols.push_back(ColOrderNode{col_index, asc});
m_lexer.skipTokenOptional(TokenType::comma);
} while (m_lexer.tokenType() != TokenType::eof); // && m_lexer.tokenType() != TokenType::keyword_offset && m_lexer.tokenType() != TokenType::keyword_limit);
}
return order_cols;
}
std::unique_ptr<Node> Parser::parse_relational_expression() {
@@ -336,7 +373,7 @@ std::unique_ptr<Node> Parser::parse_select_from_table() {
return std::make_unique<DatabaseValueNode>(tokenString);
case TokenType::keyword_null:
return std::make_unique<NullValueNode>();
default:;
default:
throw Exception("Unknown operand node");
}
}