> On Feb. 18, 2014, 6:34 p.m., Julian Hyde wrote: > > Glad to see that CURRENT_TIMESTAMP etc. are based on the query start time, > > per the SQL standard. > > > > Why the huge list of time-zones in DateUtility? A list this long is going > > to go out of date quickly, so it should be sourced from a library such > > specializes in such things. The JDK is the ideal source.
You are right the list is cumbersome. Although, this list contains the entire set of time zones supported by joda. Unless we change the version of joda this list is unlikely to change. When we want to store a timestamp in Drill we store the millisecond value in UTC and an index into this list corresponding to the timezone, so when we retrieve the timestamp we lookup the list to get the time zone and reconstruct the date-time. Saves us the hassle of storing time zone as a String or in the +/- HH:MM format. Instead of populating the list statically it might be better if I use functions from joda to populate this list though. - Mehant ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/18055/#review34726 ----------------------------------------------------------- On Feb. 18, 2014, 12:30 a.m., Mehant Baid wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/18055/ > ----------------------------------------------------------- > > (Updated Feb. 18, 2014, 12:30 a.m.) > > > Review request for drill. > > > Repository: drill-git > > > Description > ------- > > Added value vectors, holders, cast and comparison functions for the following > data types. > > Date > DateTime > Time > TimeStamp > Interval > > Internal representation of these data types: > For the data types Date, DateTime, TimeStamp we internally store milliseconds > (from epoch) in UTC. We use a 'long' to store the milliseconds. Since > TimeStamp has a timezone associated with it, we use another field (int) to > store the index of the timezone into a static list of timezones we maintain > (in DateUtility class) > > For the Time data type we again store milliseconds, but since Time has a > small range (00:00:00.000 - 23:59:59.999) we use an 'int' to store the value. > > For Interval data type, which can be used to express an interval of time > using one or more of the parameters: years, months, days, hours, minutes, > seconds, milliseconds we internally store three fields. Months (int), days > (int) and milliseconds (long). Using these three fields we can express all > the above parameters with simple conversions. Eg: Years (parameter) - Months > (internal) is a simple 1 Year = 12 months conversion. Similar conversion can > be applied to hours, minutes and seconds to convert them to milliseconds. > > Sorting, comparison functions for Date, DateTime, TimeStamp, Time are > straight forward as internally they are stored as long or int. > > In addition to these types we also have a way to represent each type as a > literal. For eg: a Date literal can be expressed using the expression: > "datetype(2008, 1, 20)", a TimeStamp literal can be expressed using the > expression: "timestamptype(2008, 1, 27, 0, 0, 0, 0, 'UTC')" and so on for all > the types. > > For performing date functions the design is to use the internal > representation to construct a Joda object (MutableDateTime) and use Joda for > date arithmetic and other functions. As an example in this patch I've added a > date_add() function that adds a Date and an Interval (DateTypeFunctions class) > > > Diffs > ----- > > > common/src/main/antlr3/org/apache/drill/common/expression/parser/ExprLexer.g > be2a3f2 > > common/src/main/antlr3/org/apache/drill/common/expression/parser/ExprParser.g > b5cf292 > > common/src/main/java/org/apache/drill/common/expression/FunctionRegistry.java > 8ffc07a > > common/src/main/java/org/apache/drill/common/expression/OutputTypeDeterminer.java > 66523c4 > > common/src/main/java/org/apache/drill/common/expression/fn/CastFunctionDefs.java > 6a98f94 > exec/java-exec/pom.xml 1c4dc32 > exec/java-exec/src/main/codegen/config.fmpp cd2b2cc > exec/java-exec/src/main/codegen/data/Casts.tdd ceb9cde > exec/java-exec/src/main/codegen/data/DateTypes.tdd PRE-CREATION > exec/java-exec/src/main/codegen/data/ValueVectorTypes.tdd 88a5974 > exec/java-exec/src/main/codegen/templates/DateCastFunctions.java > PRE-CREATION > exec/java-exec/src/main/codegen/templates/DateFunctions.java PRE-CREATION > exec/java-exec/src/main/codegen/templates/FixedValueVectors.java c357dd6 > exec/java-exec/src/main/codegen/templates/NullableValueVectors.java 051c62d > exec/java-exec/src/main/codegen/templates/ValueHolders.java 41dc049 > > exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/DateTypeFunctions.java > PRE-CREATION > > exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/impl/DateUtility.java > PRE-CREATION > exec/java-exec/src/main/java/org/apache/drill/exec/ops/FragmentContext.java > fd965a7 > > exec/java-exec/src/main/java/org/apache/drill/exec/planner/fragment/SimpleParallelizer.java > ffb4c5b > > exec/java-exec/src/test/java/org/apache/drill/exec/record/vector/TestDateTypes.java > PRE-CREATION > exec/java-exec/src/test/resources/record/vector/test_all_date_literals.json > PRE-CREATION > exec/java-exec/src/test/resources/record/vector/test_date.json PRE-CREATION > exec/java-exec/src/test/resources/record/vector/test_date_add.json > PRE-CREATION > exec/java-exec/src/test/resources/record/vector/test_datetime.json > PRE-CREATION > exec/java-exec/src/test/resources/record/vector/test_interval.json > PRE-CREATION > exec/java-exec/src/test/resources/test_simple_date.json PRE-CREATION > exec/java-exec/src/test/resources/test_simple_interval.json PRE-CREATION > protocol/src/main/java/org/apache/drill/common/types/TypeProtos.java > e4fd94a > protocol/src/main/java/org/apache/drill/exec/proto/BitControl.java 761f19f > protocol/src/main/protobuf/BitControl.proto d96f7cf > protocol/src/main/protobuf/Types.proto 3434110 > > Diff: https://reviews.apache.org/r/18055/diff/ > > > Testing > ------- > > Added unit tests and some manual testing. > > > Thanks, > > Mehant Baid > >
