Yes and no. We do use integer arithmetic, but only at a particular level of abstraction.
If DATE and TIMESTAMP functions are implemented in Java then we represent them as Java int and long values and use integer operations such as + and -. But there are also higher level rewrites that stay within the SQL type system. As far as I know, when we stay in the SQL type system we never equate DATE and TIMESTAMP to SQL INTEGER and BIGINT types. So, we would not use SqlStdOperatorTable.PLUS on DATE and TIMESTAMP values. On Thu, Sep 12, 2024 at 8:28 AM Cancai Cai <caic68...@gmail.com> wrote: > > Thank you Julian for your reply. > > I have been thinking about this seriously recently and I have another > question. The current date function calculation of calcite convert the > parameters, such as date or timestamp, convert to int or long types, finally > use the logic of operators such as SqlStdOperatorTable.PLUS to perform the > calculation? > > Is my guess correct? > > Best wishes, > Cancai Cai > > > 2024年8月27日 05:11，Norman Jordan <norman.jor...@improving.com.INVALID> 写道： > > > > Looking into this further, there is this convertlet that will convert a > > TIMESTAMP_ADD to a DATETIME_PLUS. > > https://github.com/apache/calcite/blob/main/core/src/main/java/org/apache/calcite/sql2rel/StandardConvertletTable.java#L2132 > > > > As part of it, it will convert the amount to add to a unit for > > DATETIME_PLUS. For example, hours are converted to milliseconds. > > > > From there it looks like it will convert this to a "+" operation. > > https://github.com/apache/calcite/blob/main/core/src/main/java/org/apache/calcite/adapter/enumerable/RexImpTable.java#L3718 > > > > I didn't see where it adds the two numbers together though. > > ________________________________ > > From: Cancai Cai <caic68...@gmail.com> > > Sent: Monday, August 26, 2024 8:37 AM > > To: dev@calcite.apache.org <dev@calcite.apache.org> > > Subject: Re: Some doubts about date functions > > > > Thanks for your reply. > > > > Yes, I also located here, and I finally debugged to > > https://github.com/apache/calcite/blob/main/core/src/main/java/org/apache/calcite/adapter/enumerable/RexImpTable.java#L3802 > > but I don’t know how to continue. > > > > I find it hard to believe that > > https://github.com/apache/calcite/blob/main/core/src/main/java/org/apache/calcite/util/BuiltInMethod.java#L517 > > is the processing of the data_add function, because its name is add_months > > not date_add > > > >> 2024年8月26日 23:19，Norman Jordan <norman.jor...@improving.com.INVALID> 写道： > >> > >> this leads to here: > >> https://github.com/apache/calcite/blob/main/core/src/main/java/org/apache/calcite/util/BuiltInMethod.java#L517 > >> [https://opengraph.githubassets.com/6af4884a9b80dd1ac5b81e610caea8c9e34bcc847d0e172706a503b58f4f1557/apache/calcite]<https://github.com/apache/calcite/blob/main/core/src/main/java/org/apache/calcite/util/BuiltInMethod.java#L517> > >> calcite/core/src/main/java/org/apache/calcite/util/BuiltInMethod.java at > >> main ・ > > > > Warning: The sender of this message could not be validated and may not be > > the actual sender. >
