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This commit is contained in:
alesapin 2019-12-29 14:25:26 +03:00
parent 247906a4d7
commit 44370467f0
2 changed files with 22 additions and 13 deletions
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10
dbms/src/Storages/AlterCommands.cpp
View File

@ -392,8 +392,9 @@ void AlterCommand::apply(StorageInMemoryMetadata & metadata) const
for (const auto & change : settings_changes)
{
auto finder = [&change](const SettingChange & c) { return c.name == change.name; };
if (auto it = std::find_if(settings_from_storage.begin(), settings_from_storage.end(), finder);
it != settings_from_storage.end())
auto it = std::find_if(settings_from_storage.begin(), settings_from_storage.end(), finder);
if (it != settings_from_storage.end())
it->value = change.value;
else
settings_from_storage.push_back(change);
@ -644,11 +645,6 @@ void AlterCommands::prepare(const StorageInMemoryMetadata & metadata, const Cont
void AlterCommands::validate(const StorageInMemoryMetadata & metadata, const Context & context) const
{
/// We will save ALTER ADD/MODIFY command indices (only the last for each column) for possible modification
/// (we might need to add deduced types or modify default expressions).
/// Saving indices because we can add new commands later and thus cause vector resize.
std::unordered_map<String, size_t> column_to_command_idx;
for (size_t i = 0; i < size(); ++i)
{
auto & command = (*this)[i];

25
dbms/src/Storages/AlterCommands.h
View File

@ -96,32 +96,45 @@ struct AlterCommand
/// in each part on disk (it's not lightweight alter).
bool isModifyingData() const;
/// checks that only settings changed by alter
/// Checks that only settings changed by alter
bool isSettingsAlter() const;
/// Checks that only comment changed by alter
bool isCommentAlter() const;
};
/// Return string representation of AlterCommand::Type
String alterTypeToString(const AlterCommand::Type type);
class Context;
/// Vector of AlterCommand with several additional functions
class AlterCommands : public std::vector<AlterCommand>
{
private:
bool prepared = false;
public:
void apply(StorageInMemoryMetadata & metadata) const;
void prepare(const StorageInMemoryMetadata & metadata, const Context & context);
/// Validate that commands can be applied to metadata.
/// Checks that all columns exist and dependecies between them.
/// This check is lightweight and base only on metadata.
/// More accurate check have to be performed with storage->checkAlterIsPossible.
void validate(const StorageInMemoryMetadata & metadata, const Context & context) const;
/// Prepare alter commands. Set ignore flag to some of them
/// and additional commands for dependent columns.
void prepare(const StorageInMemoryMetadata & metadata, const Context & context);
/// Apply all alter command in sequential order to storage metadata.
/// Commands have to be prepared before apply.
void apply(StorageInMemoryMetadata & metadata) const;
/// At least one command modify data on disk.
bool isModifyingData() const;
/// At least one command modify settings.
bool isSettingsAlter() const;
/// At least one command modify comments.
bool isCommentAlter() const;
};