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support ASOF JOIN ON syntax
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chertus
parent
c4f1038efc
commit
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210
dbms/src/Interpreters/CollectJoinOnKeysVisitor.cpp
Normal file
210
dbms/src/Interpreters/CollectJoinOnKeysVisitor.cpp
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@ -0,0 +1,210 @@
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#include <Parsers/queryToString.h>
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#include <Interpreters/CollectJoinOnKeysVisitor.h>
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#include <Interpreters/IdentifierSemantic.h>
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#include <Interpreters/AnalyzedJoin.h>
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namespace DB
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{
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namespace ErrorCodes
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{
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extern const int INVALID_JOIN_ON_EXPRESSION;
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extern const int AMBIGUOUS_COLUMN_NAME;
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extern const int NOT_IMPLEMENTED;
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extern const int LOGICAL_ERROR;
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}
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void CollectJoinOnKeysMatcher::Data::addJoinKeys(const ASTPtr & left_ast, const ASTPtr & right_ast,
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const std::pair<size_t, size_t> & table_no)
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{
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ASTPtr left = left_ast->clone();
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ASTPtr right = right_ast->clone();
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if (table_no.first == 1 || table_no.second == 2)
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analyzed_join.addOnKeys(left, right);
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else if (table_no.first == 2 || table_no.second == 1)
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analyzed_join.addOnKeys(right, left);
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else
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throw Exception("Cannot detect left and right JOIN keys. JOIN ON section is ambiguous.",
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ErrorCodes::AMBIGUOUS_COLUMN_NAME);
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has_some = true;
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}
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void CollectJoinOnKeysMatcher::Data::addAsofJoinKeys(const ASTPtr & left_ast, const ASTPtr & right_ast,
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const std::pair<size_t, size_t> & table_no)
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{
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if (table_no.first == 1 || table_no.second == 2)
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{
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asof_left_key = left_ast->clone();
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asof_right_key = right_ast->clone();
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return;
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}
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throw Exception("ASOF JOIN for (left_table.x <= right_table.x) is not implemented", ErrorCodes::NOT_IMPLEMENTED);
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}
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void CollectJoinOnKeysMatcher::Data::asofToJoinKeys()
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{
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if (!asof_left_key || !asof_right_key)
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throw Exception("No inequality in ASOF JOIN ON section.", ErrorCodes::INVALID_JOIN_ON_EXPRESSION);
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addJoinKeys(asof_left_key, asof_right_key, {1, 2});
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}
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void CollectJoinOnKeysMatcher::visit(const ASTFunction & func, const ASTPtr & ast, Data & data)
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{
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if (func.name == "and")
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return; /// go into children
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if (func.name == "equals")
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{
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ASTPtr left = func.arguments->children.at(0);
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ASTPtr right = func.arguments->children.at(1);
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auto table_numbers = getTableNumbers(ast, left, right, data);
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data.addJoinKeys(left, right, table_numbers);
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return;
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}
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bool less_or_equals = (func.name == "lessOrEquals");
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bool greater_or_equals = (func.name == "greaterOrEquals");
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if (data.is_asof && (less_or_equals || greater_or_equals))
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{
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if (data.asof_left_key || data.asof_right_key)
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throwSyntaxException("ASOF JOIN expects exactly one inequality in ON section, unexpected " + queryToString(ast) + ".");
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ASTPtr left = func.arguments->children.at(0);
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ASTPtr right = func.arguments->children.at(1);
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auto table_numbers = getTableNumbers(ast, left, right, data);
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if (greater_or_equals)
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data.addAsofJoinKeys(left, right, table_numbers);
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else
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data.addAsofJoinKeys(right, left, std::make_pair(table_numbers.second, table_numbers.first));
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return;
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}
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throwSyntaxException("Expected equals expression, got " + queryToString(ast) + ".");
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}
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void CollectJoinOnKeysMatcher::getIdentifiers(const ASTPtr & ast, std::vector<const ASTIdentifier *> & out)
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{
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if (const auto * ident = ast->as<ASTIdentifier>())
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{
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if (IdentifierSemantic::getColumnName(*ident))
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out.push_back(ident);
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return;
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}
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for (const auto & child : ast->children)
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getIdentifiers(child, out);
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}
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std::pair<size_t, size_t> CollectJoinOnKeysMatcher::getTableNumbers(const ASTPtr & expr, const ASTPtr & left_ast, const ASTPtr & right_ast,
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Data & data)
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{
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std::vector<const ASTIdentifier *> left_identifiers;
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std::vector<const ASTIdentifier *> right_identifiers;
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getIdentifiers(left_ast, left_identifiers);
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getIdentifiers(right_ast, right_identifiers);
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size_t left_idents_table = getTableForIdentifiers(left_identifiers, data);
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size_t right_idents_table = getTableForIdentifiers(right_identifiers, data);
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if (left_idents_table && left_idents_table == right_idents_table)
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{
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auto left_name = queryToString(*left_identifiers[0]);
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auto right_name = queryToString(*right_identifiers[0]);
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throwSyntaxException("In expression " + queryToString(expr) + " columns " + left_name + " and " + right_name
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+ " are from the same table but from different arguments of equal function.");
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}
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return std::make_pair(left_idents_table, right_idents_table);
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}
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const ASTIdentifier * CollectJoinOnKeysMatcher::unrollAliases(const ASTIdentifier * identifier, const Aliases & aliases)
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{
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if (identifier->compound())
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return identifier;
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UInt32 max_attempts = 100;
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for (auto it = aliases.find(identifier->name); it != aliases.end();)
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{
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const ASTIdentifier * parent = identifier;
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identifier = it->second->as<ASTIdentifier>();
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if (!identifier)
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break; /// not a column alias
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if (identifier == parent)
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break; /// alias to itself with the same name: 'a as a'
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if (identifier->compound())
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break; /// not an alias. Break to prevent cycle through short names: 'a as b, t1.b as a'
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it = aliases.find(identifier->name);
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if (!max_attempts--)
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throw Exception("Cannot unroll aliases for '" + identifier->name + "'", ErrorCodes::LOGICAL_ERROR);
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}
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return identifier;
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}
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/// @returns 1 if identifiers belongs to left table, 2 for right table and 0 if unknown. Throws on table mix.
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/// Place detected identifier into identifiers[0] if any.
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size_t CollectJoinOnKeysMatcher::getTableForIdentifiers(std::vector<const ASTIdentifier *> & identifiers, const Data & data)
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{
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size_t table_number = 0;
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for (auto & ident : identifiers)
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{
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const ASTIdentifier * identifier = unrollAliases(ident, data.aliases);
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if (!identifier)
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continue;
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/// Column name could be cropped to a short form in TranslateQualifiedNamesVisitor.
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/// In this case it saves membership in IdentifierSemantic.
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size_t membership = IdentifierSemantic::getMembership(*identifier);
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if (!membership)
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{
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const String & name = identifier->name;
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bool in_left_table = data.source_columns.count(name);
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bool in_right_table = data.joined_columns.count(name);
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if (in_left_table && in_right_table)
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throw Exception("Column '" + name + "' is ambiguous", ErrorCodes::AMBIGUOUS_COLUMN_NAME);
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if (in_left_table)
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membership = 1;
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if (in_right_table)
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membership = 2;
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}
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if (membership && table_number == 0)
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{
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table_number = membership;
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std::swap(ident, identifiers[0]); /// move first detected identifier to the first position
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}
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if (membership && membership != table_number)
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{
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throw Exception("Invalid columns in JOIN ON section. Columns "
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+ identifiers[0]->getAliasOrColumnName() + " and " + ident->getAliasOrColumnName()
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+ " are from different tables.", ErrorCodes::INVALID_JOIN_ON_EXPRESSION);
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}
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}
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return table_number;
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}
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[[noreturn]] void CollectJoinOnKeysMatcher::throwSyntaxException(const String & msg)
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{
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throw Exception("Invalid expression for JOIN ON. " + msg +
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" Supported syntax: JOIN ON Expr([table.]column, ...) = Expr([table.]column, ...) "
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"[AND Expr([table.]column, ...) = Expr([table.]column, ...) ...]",
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ErrorCodes::INVALID_JOIN_ON_EXPRESSION);
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}
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}
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@ -1,23 +1,16 @@
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#pragma once
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#include <Core/Names.h>
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#include <Parsers/ASTFunction.h>
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#include <Parsers/queryToString.h>
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#include <Interpreters/InDepthNodeVisitor.h>
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#include <Interpreters/Aliases.h>
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#include <Interpreters/SyntaxAnalyzer.h>
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namespace DB
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{
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namespace ErrorCodes
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{
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extern const int INVALID_JOIN_ON_EXPRESSION;
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extern const int AMBIGUOUS_COLUMN_NAME;
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extern const int LOGICAL_ERROR;
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}
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class ASTIdentifier;
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struct AnalyzedJoin;
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class CollectJoinOnKeysMatcher
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{
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@ -30,7 +23,14 @@ public:
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const NameSet & source_columns;
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const NameSet & joined_columns;
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const Aliases & aliases;
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bool has_some = false;
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const bool is_asof;
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ASTPtr asof_left_key{};
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ASTPtr asof_right_key{};
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bool has_some{false};
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void addJoinKeys(const ASTPtr & left_ast, const ASTPtr & right_ast, const std::pair<size_t, size_t> & table_no);
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void addAsofJoinKeys(const ASTPtr & left_ast, const ASTPtr & right_ast, const std::pair<size_t, size_t> & table_no);
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void asofToJoinKeys();
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};
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static void visit(const ASTPtr & ast, Data & data)
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@ -48,146 +48,14 @@ public:
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}
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private:
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static void visit(const ASTFunction & func, const ASTPtr & ast, Data & data)
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{
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if (func.name == "and")
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return; /// go into children
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static void visit(const ASTFunction & func, const ASTPtr & ast, Data & data);
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if (func.name == "equals")
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{
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ASTPtr left = func.arguments->children.at(0)->clone();
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ASTPtr right = func.arguments->children.at(1)->clone();
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addJoinKeys(ast, left, right, data);
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return;
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}
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static void getIdentifiers(const ASTPtr & ast, std::vector<const ASTIdentifier *> & out);
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static std::pair<size_t, size_t> getTableNumbers(const ASTPtr & expr, const ASTPtr & left_ast, const ASTPtr & right_ast, Data & data);
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static const ASTIdentifier * unrollAliases(const ASTIdentifier * identifier, const Aliases & aliases);
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static size_t getTableForIdentifiers(std::vector<const ASTIdentifier *> & identifiers, const Data & data);
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throwSyntaxException("Expected equals expression, got " + queryToString(ast) + ".");
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}
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static void getIdentifiers(const ASTPtr & ast, std::vector<const ASTIdentifier *> & out)
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{
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if (const auto * ident = ast->as<ASTIdentifier>())
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{
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if (IdentifierSemantic::getColumnName(*ident))
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out.push_back(ident);
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return;
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}
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for (const auto & child : ast->children)
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getIdentifiers(child, out);
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}
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static void addJoinKeys(const ASTPtr & expr, ASTPtr left_ast, ASTPtr right_ast, Data & data)
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{
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std::vector<const ASTIdentifier *> left_identifiers;
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std::vector<const ASTIdentifier *> right_identifiers;
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getIdentifiers(left_ast, left_identifiers);
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getIdentifiers(right_ast, right_identifiers);
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size_t left_idents_table = getTableForIdentifiers(left_identifiers, data);
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size_t right_idents_table = getTableForIdentifiers(right_identifiers, data);
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if (left_idents_table && left_idents_table == right_idents_table)
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{
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auto left_name = queryToString(*left_identifiers[0]);
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auto right_name = queryToString(*right_identifiers[0]);
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throwSyntaxException("In expression " + queryToString(expr) + " columns " + left_name + " and " + right_name
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+ " are from the same table but from different arguments of equal function.");
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}
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if (left_idents_table == 1 || right_idents_table == 2)
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data.analyzed_join.addOnKeys(left_ast, right_ast);
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else if (left_idents_table == 2 || right_idents_table == 1)
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data.analyzed_join.addOnKeys(right_ast, left_ast);
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else
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throw Exception("Cannot detect left and right JOIN keys. JOIN ON section is ambiguous.",
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ErrorCodes::AMBIGUOUS_COLUMN_NAME);
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data.has_some = true;
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}
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static const ASTIdentifier * unrollAliases(const ASTIdentifier * identifier, const Aliases & aliases)
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{
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if (identifier->compound())
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return identifier;
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UInt32 max_attempts = 100;
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for (auto it = aliases.find(identifier->name); it != aliases.end();)
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{
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const ASTIdentifier * parent = identifier;
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identifier = it->second->as<ASTIdentifier>();
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if (!identifier)
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break; /// not a column alias
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if (identifier == parent)
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break; /// alias to itself with the same name: 'a as a'
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if (identifier->compound())
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break; /// not an alias. Break to prevent cycle through short names: 'a as b, t1.b as a'
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it = aliases.find(identifier->name);
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if (!max_attempts--)
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throw Exception("Cannot unroll aliases for '" + identifier->name + "'", ErrorCodes::LOGICAL_ERROR);
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}
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return identifier;
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}
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/// @returns 1 if identifiers belongs to left table, 2 for right table and 0 if unknown. Throws on table mix.
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/// Place detected identifier into identifiers[0] if any.
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static size_t getTableForIdentifiers(std::vector<const ASTIdentifier *> & identifiers, const Data & data)
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{
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size_t table_number = 0;
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for (auto & ident : identifiers)
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{
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const ASTIdentifier * identifier = unrollAliases(ident, data.aliases);
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if (!identifier)
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continue;
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/// Column name could be cropped to a short form in TranslateQualifiedNamesVisitor.
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/// In this case it saves membership in IdentifierSemantic.
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size_t membership = IdentifierSemantic::getMembership(*identifier);
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if (!membership)
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{
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const String & name = identifier->name;
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bool in_left_table = data.source_columns.count(name);
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bool in_right_table = data.joined_columns.count(name);
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if (in_left_table && in_right_table)
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throw Exception("Column '" + name + "' is ambiguous", ErrorCodes::AMBIGUOUS_COLUMN_NAME);
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if (in_left_table)
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membership = 1;
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if (in_right_table)
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membership = 2;
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}
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if (membership && table_number == 0)
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{
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table_number = membership;
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std::swap(ident, identifiers[0]); /// move first detected identifier to the first position
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}
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if (membership && membership != table_number)
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{
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throw Exception("Invalid columns in JOIN ON section. Columns "
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+ identifiers[0]->getAliasOrColumnName() + " and " + ident->getAliasOrColumnName()
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+ " are from different tables.", ErrorCodes::INVALID_JOIN_ON_EXPRESSION);
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}
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}
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return table_number;
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}
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[[noreturn]] static void throwSyntaxException(const String & msg)
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{
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throw Exception("Invalid expression for JOIN ON. " + msg +
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" Supported syntax: JOIN ON Expr([table.]column, ...) = Expr([table.]column, ...) "
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"[AND Expr([table.]column, ...) = Expr([table.]column, ...) ...]",
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ErrorCodes::INVALID_JOIN_ON_EXPRESSION);
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}
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[[noreturn]] static void throwSyntaxException(const String & msg);
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};
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/// Parse JOIN ON expression and collect ASTs for joined columns.
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@ -22,6 +22,7 @@
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#include <Parsers/ASTTablesInSelectQuery.h>
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#include <Parsers/ParserTablesInSelectQuery.h>
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#include <Parsers/parseQuery.h>
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#include <Parsers/queryToString.h>
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#include <DataTypes/NestedUtils.h>
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@ -509,11 +510,14 @@ void collectJoinedColumns(AnalyzedJoin & analyzed_join, const ASTSelectQuery & s
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for (const auto & col : analyzed_join.columns_from_joined_table)
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joined_columns.insert(col.original_name);
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CollectJoinOnKeysVisitor::Data data{analyzed_join, source_columns, joined_columns, aliases};
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bool is_asof = (table_join.strictness == ASTTableJoin::Strictness::Asof);
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CollectJoinOnKeysVisitor::Data data{analyzed_join, source_columns, joined_columns, aliases, is_asof};
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CollectJoinOnKeysVisitor(data).visit(table_join.on_expression);
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if (!data.has_some)
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throw Exception("Cannot get JOIN keys from JOIN ON section: " + queryToString(table_join.on_expression),
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ErrorCodes::INVALID_JOIN_ON_EXPRESSION);
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if (is_asof)
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data.asofToJoinKeys();
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}
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bool make_nullable = join_use_nulls && isLeftOrFull(table_join.kind);
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@ -12,7 +12,7 @@ INSERT INTO B(k,t,b) VALUES (2,3,3);
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SELECT A.k, toString(A.t, 'UTC'), A.a, B.b, toString(B.t, 'UTC'), B.k FROM A ASOF LEFT JOIN B USING(k,t) ORDER BY (A.k, A.t);
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SELECT A.k, toString(A.t, 'UTC'), A.a, B.b, toString(B.t, 'UTC'), B.k FROM A ASOF INNER JOIN B ON A.k == B.k AND A.t == B.t ORDER BY (A.k, A.t);
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SELECT A.k, toString(A.t, 'UTC'), A.a, B.b, toString(B.t, 'UTC'), B.k FROM A ASOF INNER JOIN B ON A.k == B.k AND A.t >= B.t ORDER BY (A.k, A.t);
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SELECT A.k, toString(A.t, 'UTC'), A.a, B.b, toString(B.t, 'UTC'), B.k FROM A ASOF JOIN B USING(k,t) ORDER BY (A.k, A.t);
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||||
|
||||
13
dbms/tests/queries/0_stateless/00976_asof_join_on.reference
Normal file
13
dbms/tests/queries/0_stateless/00976_asof_join_on.reference
Normal file
@ -0,0 +1,13 @@
|
||||
1 1 0 0
|
||||
1 2 1 2
|
||||
1 3 1 2
|
||||
2 1 0 0
|
||||
2 2 0 0
|
||||
2 3 2 3
|
||||
3 1 0 0
|
||||
3 2 0 0
|
||||
3 3 0 0
|
||||
9
|
||||
1 2 1 2
|
||||
1 3 1 2
|
||||
2 3 2 3
|
||||
21
dbms/tests/queries/0_stateless/00976_asof_join_on.sql
Normal file
21
dbms/tests/queries/0_stateless/00976_asof_join_on.sql
Normal file
@ -0,0 +1,21 @@
|
||||
DROP TABLE IF EXISTS A;
|
||||
DROP TABLE IF EXISTS B;
|
||||
|
||||
CREATE TABLE A(a UInt32, t UInt32) ENGINE = Memory;
|
||||
CREATE TABLE B(b UInt32, t UInt32) ENGINE = Memory;
|
||||
|
||||
INSERT INTO A (a,t) VALUES (1,1),(1,2),(1,3), (2,1),(2,2),(2,3), (3,1),(3,2),(3,3);
|
||||
INSERT INTO B (b,t) VALUES (1,2),(1,4),(2,3);
|
||||
|
||||
SELECT A.a, A.t, B.b, B.t FROM A ASOF LEFT JOIN B ON A.a == B.b AND A.t >= B.t ORDER BY (A.a, A.t);
|
||||
SELECT count() FROM A ASOF LEFT JOIN B ON A.a == B.b AND B.t <= A.t;
|
||||
SELECT A.a, A.t, B.b, B.t FROM A ASOF INNER JOIN B ON B.t <= A.t AND A.a == B.b;
|
||||
SELECT count() FROM A ASOF JOIN B ON A.a == B.b AND A.t <= B.t; -- { serverError 48 }
|
||||
SELECT count() FROM A ASOF JOIN B ON A.a == B.b AND B.t >= A.t; -- { serverError 48 }
|
||||
SELECT count() FROM A ASOF JOIN B ON A.a == B.b AND A.t > B.t; -- { serverError 403 }
|
||||
SELECT count() FROM A ASOF JOIN B ON A.a == B.b AND A.t < B.t; -- { serverError 403 }
|
||||
SELECT count() FROM A ASOF JOIN B ON A.a == B.b AND A.t == B.t; -- { serverError 403 }
|
||||
SELECT count() FROM A ASOF JOIN B ON A.a == B.b AND A.t != B.t; -- { serverError 403 }
|
||||
|
||||
DROP TABLE A;
|
||||
DROP TABLE B;
|
||||
Loading…
Reference in New Issue
Block a user