varchar tasks

[bluestreak01]

MUST HAVE

• [x] Run ingestion benchmark with varchar
• [x] Run Clickbench with varchar instead of String
• [x] plan to switch users over to VARCHAR
• [x] Documentation: Documentation should be changed to prefer VARCHAR over STRING at all places.
• [x] Web console support. @jerrinot: https://github.com/questdb/ui/pull/281
• [x] TextImport deals incorrectly with quotes when importing into a VarChar column @jerrinot https://github.com/questdb/questdb/pull/4476

NICE TO HAVE

• [ ] JIT support for varchar_col equals, substring equals, starts with, regexp (this might be moved to MUST HAVE, depending on benchmarking)
• [ ] add varchar variants of io.questdb.griffin.engine.functions.regex SQL functions
• [ ] to_uppercase(varchar) currently produces a string. this is unexpected. not sure if this is a blocker.
• [x] web console to understand rnd_varchar(): @jerrinot https://github.com/questdb/sql-grammar/pull/34
• [ ] Varchar equivalent of RndStrRndListFunctionFactory

COMPLETED

• [x] add varchar variants of SQL functions: quote_ident, split_part @nwoolmer https://github.com/questdb/questdb/issues/4360
• [x] Validate out of the box behaviour for all protocols: REST, PgWire, ILP. ILP should create VARCHAR columns by default + compatibility flag to revert back to STRING. @jerrinot https://github.com/questdb/questdb/pull/4475
• [x] alter table alter column type @ideoma #4413
• [x] support for VARCHAR in WhereClauseParser (timestamp search by VARCHAR) ~@jerrinot~ ~@bluestreak01~ @jerrinot https://github.com/questdb/questdb/pull/4403
• [x] AbstractTextLexer doesn't calculate ASCII flag, so all inserted varchars have us.isAscii() == false. We need to fix that @bluestreak01 in https://github.com/questdb/questdb/pull/4401
• [x] varchar update bug @puzpuzpuz #4353

create table xyz as (select rnd_str(2,5,1) a, timestamp_sequence(0, 1000) ts from long_sequence(10000)) timestamp(ts) partition by DAY;
alter table xyz add column b varchar;
update xyz set b = a;

select count(*) from xyz where a is not null;
select count(*) from xyz where b is not null;

• [x] support in InTimestampTimestampFunctionFactory @jerrinot https://github.com/questdb/questdb/pull/4415
• [x] add varchar variants of str aggregate functions such as min/max
• [x] JIT support for varchar_col IS NULL/IS NOT NULL @puzpuzpuz #4357
• [x] cast varchar to geohashes @mtopolnik
• [x] cast varchar to ipv4 ~@jerrinot~ @mtopolnik
• [x] string vs varchar consistency when casting to timestamp @jerrinot https://github.com/questdb/questdb/pull/4408
• [x] add varchar variants of SQL functions: trim, ltrim, rtrim, strpos, position, replace @mtopolnik #4430
• [x] add varchar variant of SQL function: starts_with @mtopolnik https://github.com/questdb/questdb/pull/4453
• [x] introduce single varchar key unordered map; the map can leverage stable pointers infra introduced recently to avoid copying varchars into map memory - instead it'll be storing pointers to mmapped memory @jerrinot https://github.com/questdb/questdb/pull/4435
• [x] Unify access to VARCHAR column, whether inlined or split, in a single class. @mtopolnik https://github.com/questdb/questdb/pull/4453
• [x] length(varchar) is dog-slow: we should calculate the raw size - number of continuation bytes instead of doing proper UTF-8 parsing; ideally that should be done with SWAR @mtopolnik #4442

[nwoolmer]

Related issue: https://github.com/questdb/questdb/issues/4262