ClickHouse/src/Interpreters/DatabaseAndTableWithAlias.h
2022-11-02 06:21:02 +00:00

100 lines
3.2 KiB
C++

#pragma once
#include <Core/Names.h>
#include <base/types.h>
#include <Core/NamesAndTypes.h>
#include <Parsers/IAST_fwd.h>
#include <memory>
#include <optional>
#include <Core/UUID.h>
namespace DB
{
class ASTSelectQuery;
class ASTIdentifier;
class ASTTableIdentifier;
struct ASTTableExpression;
/// Extracts database name (and/or alias) from table expression or identifier
struct DatabaseAndTableWithAlias
{
// TODO(ilezhankin): replace with ASTTableIdentifier
String database;
String table;
String alias;
UUID uuid = UUIDHelpers::Nil;
DatabaseAndTableWithAlias() = default;
explicit DatabaseAndTableWithAlias(const ASTPtr & identifier_node, const String & current_database = "");
explicit DatabaseAndTableWithAlias(const ASTIdentifier & identifier, const String & current_database = "");
explicit DatabaseAndTableWithAlias(const ASTTableIdentifier & identifier, const String & current_database = "");
explicit DatabaseAndTableWithAlias(const ASTTableExpression & table_expression, const String & current_database = "");
/// "alias." or "table." if alias is empty
String getQualifiedNamePrefix(bool with_dot = true) const;
/// Check if it satisfies another db_table name. @note opterion is not symmetric.
bool satisfies(const DatabaseAndTableWithAlias & table, bool table_may_be_an_alias) const;
/// Exactly the same table name
bool same(const DatabaseAndTableWithAlias & db_table) const
{
return database == db_table.database && table == db_table.table && alias == db_table.alias && uuid == db_table.uuid;
}
};
struct TableWithColumnNamesAndTypes
{
DatabaseAndTableWithAlias table;
NamesAndTypesList columns;
NamesAndTypesList hidden_columns; /// Not general columns like MATERIALIZED, ALIAS, VIRTUAL. They are omitted in * and t.* results by default.
NamesAndTypesList alias_columns;
NamesAndTypesList materialized_columns;
TableWithColumnNamesAndTypes(const DatabaseAndTableWithAlias & table_, const NamesAndTypesList & columns_)
: table(table_)
, columns(columns_)
{
for (auto & col : columns)
names.insert(col.name);
}
bool hasColumn(const String & name) const { return names.contains(name); }
void addHiddenColumns(const NamesAndTypesList & addition)
{
addAdditionalColumns(hidden_columns, addition);
}
void addAliasColumns(const NamesAndTypesList & addition)
{
addAdditionalColumns(alias_columns, addition);
}
void addMaterializedColumns(const NamesAndTypesList & addition)
{
addAdditionalColumns(materialized_columns, addition);
}
private:
void addAdditionalColumns(NamesAndTypesList & target, const NamesAndTypesList & addition)
{
target.insert(target.end(), addition.begin(), addition.end());
for (const auto & col : addition)
names.insert(col.name);
}
NameSet names;
};
std::vector<DatabaseAndTableWithAlias> getDatabaseAndTables(const ASTSelectQuery & select_query, const String & current_database);
std::optional<DatabaseAndTableWithAlias> getDatabaseAndTable(const ASTSelectQuery & select, size_t table_number);
using TablesWithColumns = std::vector<TableWithColumnNamesAndTypes>;
}