Allowed to switch between 'basic' and 'best effort' methods of parsing DateTime from text #1710

dbms/src/DataStreams/FormatFactory.cpp

@@ -55,6 +55,7 @@ BlockInputStreamPtr FormatFactory::getInput(const String & name, ReadBuffer & bu
     format_settings.csv.delimiter = settings.format_csv_delimiter;
     format_settings.values.interpret_expressions = settings.input_format_values_interpret_expressions;
     format_settings.skip_unknown_fields = settings.input_format_skip_unknown_fields;
+    format_settings.date_time_input_format = settings.date_time_input_format;
 
     auto wrap_row_stream = [&](auto && row_stream)
     {

dbms/src/Interpreters/Settings.h

@@ -262,6 +262,8 @@ struct Settings
     M(SettingUInt64, max_network_bandwidth_for_all_users, 0, "The maximum speed of data exchange over the network in bytes per second for all concurrently running queries. Zero means unlimited.") \
     M(SettingChar, format_csv_delimiter, ',', "The character to be considered as a delimiter in CSV data. If setting with a string, a string has to have a length of 1.") \
     M(SettingUInt64, enable_conditional_computation, 0, "Enable conditional computations") \
+    \
+    M(SettingDateTimeInputFormat, date_time_input_format, FormatSettings::DateTimeInputFormat::Basic, "Method to read DateTime from text input formats. Possible values: 'basic' and 'best_effort'.") \
 
 #define DECLARE(TYPE, NAME, DEFAULT, DESCRIPTION) \
     TYPE NAME {DEFAULT};

dbms/src/Interpreters/SettingsCommon.cpp

@@ -23,6 +23,7 @@ namespace ErrorCodes
     extern const int UNKNOWN_DISTRIBUTED_PRODUCT_MODE;
     extern const int UNKNOWN_GLOBAL_SUBQUERIES_METHOD;
     extern const int SIZE_OF_FIXED_STRING_DOESNT_MATCH;
+    extern const int BAD_ARGUMENTS;
 }
 
 template <typename IntType>
@@ -580,4 +581,49 @@ void SettingChar::write(WriteBuffer & buf) const
     writeBinary(toString(), buf);
 }
 
+
+SettingDateTimeInputFormat::Value SettingDateTimeInputFormat::getValue(const String & s)
+{
+    if (s == "basic")  return Value::Basic;
+    if (s == "best_effort")  return Value::BestEffort;
+
+    throw Exception("Unknown DateTime input format: '" + s + "', must be one of 'basic', 'best_effort'", ErrorCodes::BAD_ARGUMENTS);
+}
+
+String SettingDateTimeInputFormat::toString() const
+{
+    const char * strings[] = {"basic", "best_effort"};
+    if (value < Value::Basic || value > Value::BestEffort)
+        throw Exception("Unknown DateTime input format", ErrorCodes::BAD_ARGUMENTS);
+    return strings[static_cast<size_t>(value)];
+}
+
+void SettingDateTimeInputFormat::set(Value x)
+{
+    value = x;
+    changed = true;
+}
+
+void SettingDateTimeInputFormat::set(const Field & x)
+{
+    set(safeGet<const String &>(x));
+}
+
+void SettingDateTimeInputFormat::set(const String & x)
+{
+    set(getValue(x));
+}
+
+void SettingDateTimeInputFormat::set(ReadBuffer & buf)
+{
+    String x;
+    readBinary(x, buf);
+    set(x);
+}
+
+void SettingDateTimeInputFormat::write(WriteBuffer & buf) const
+{
+    writeBinary(toString(), buf);
+}
+
 }

dbms/src/Interpreters/SettingsCommon.h

@@ -2,6 +2,7 @@
 
 #include <Poco/Timespan.h>
 #include <DataStreams/SizeLimits.h>
+#include <DataTypes/FormatSettings.h>
 #include <IO/CompressedStream.h>
 #include <Core/Types.h>
 
@@ -348,4 +349,28 @@ public:
     void write(WriteBuffer & buf) const;
 };
 
+
+struct SettingDateTimeInputFormat
+{
+    using Value = FormatSettings::DateTimeInputFormat;
+
+    Value value;
+    bool changed = false;
+
+    SettingDateTimeInputFormat(Value x) : value(x) {}
+
+    operator Value() const { return value; }
+    SettingDateTimeInputFormat & operator= (Value x) { set(x); return *this; }
+
+    static Value getValue(const String & s);
+
+    String toString() const;
+
+    void set(Value x);
+    void set(const Field & x);
+    void set(const String & x);
+    void set(ReadBuffer & buf);
+    void write(WriteBuffer & buf) const;
+};
+
 }