ref-docs: sql: fix BCE timestamptz wire format for LMT-affected zones

src/current/v26.1/statements.md

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+---
+title: sql: fix BCE timestamptz wire format for LMT-affected zones
+summary: Enhanced Functionality
+toc: true
+docs_area: reference.sql
+---
+
+## Enhanced Functionality
+
+### Timezone Abbreviation Parsing Support
+
+CockroachDB now supports timezone abbreviations in timestamp literals, which previously returned "unimplemented" errors.
+
+**Examples**:
+
+{% include_cached copy-clipboard.html %}
+~~~ sql
+-- Timezone abbreviations now work in timestamptz literals
+SELECT '2014-07-15 08:15:23 EST'::timestamptz;
+----
+2014-07-15 08:15:23-05
+
+SELECT '2014-07-15 08:15:23 PST'::timestamptz;
+----
+2014-07-15 08:15:23-08
+
+-- Case-insensitive parsing
+SELECT '2014-07-15 08:15:23 est'::timestamptz;
+----
+2014-07-15 08:15:23-05
+~~~
+
+### pg_timezone_abbrevs System Table
+
+The `pg_catalog.pg_timezone_abbrevs` system table is now fully implemented and lists timezone abbreviations recognized by date/time literal parsing.
+
+**Example**:
+
+{% include_cached copy-clipboard.html %}
+~~~ sql
+SELECT abbrev, utc_offset, is_dst
+FROM pg_catalog.pg_timezone_abbrevs
+WHERE abbrev IN ('EST', 'EDT', 'PST', 'PDT')
+ORDER BY abbrev;
+----
+abbrev | utc_offset | is_dst
+-------+------------+-------
+EDT    | -04:00:00  | true
+EST    | -05:00:00  | false
+PDT    | -07:00:00  | true
+PST    | -08:00:00  | false
+~~~
+
+### Improved BCE (Before Common Era) Date Handling
+
+The `make_date`, `make_timestamp`, and `make_timestamptz` functions now handle BCE dates more consistently with PostgreSQL standards.
+
+**Examples**:
+
+{% include_cached copy-clipboard.html %}
+~~~ sql
+-- Negative years represent BCE dates
+SELECT make_date(-2013, 7, 15);
+----
+2013-07-15 BC
+
+-- Year -1 maps to 1 BC (no year zero in SQL semantics)
+SELECT make_date(-1, 1, 1);
+----
+0001-01-01 BC
+
+SELECT make_timestamp(-2013, 7, 15, 8, 15, 23.5);
+----
+2013-07-15 08:15:23.5 BC
+
+SELECT make_timestamptz(-2013, 7, 15, 8, 15, 23.5);
+----
+2013-07-15 08:15:23.5-05 BC
+~~~
+
+### Updated Function Descriptions
+
+The function descriptions for date/time creation functions have been simplified to remove references to ISO 8601 formatting, focusing on their core functionality:
+
+- `make_date()`: Create date from year, month, and day fields (negative years signify BC)
+- `make_timestamp()`: Create timestamp from year, month, day, hour, minute, and seconds fields (negative years signify BC)  
+- `make_timestamptz()`: Create timestamp with time zone from year, month, day, hour, minute and seconds fields (negative years signify BC)
+
+These improvements enhance CockroachDB's PostgreSQL compatibility, particularly for applications that rely on timezone abbreviations or work with historical dates.