Data update

Task/Substring/DuckDB/substring.duckdb

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+# For brevity, we will use a table-valued function for defining the sample string(s):
+create or replace function s() as table (select '一二三四五六七八九十' as s);
+
+# starting from n characters in and of m length:  s[n: n+m-1]
+select  s[1:2] from s();
+
+# starting from n characters in, up to the end of the string:  s[n:]
+select  s[9:] from s();
+
+# whole string minus the last character: .[:-2]
+select  s[0:-2] from s();
+
+# starting from a known character within the string and of m length, say 2:
+select  s[ix:ix+(2-1)] from (select s, position('五' in s) as ix from s());
+
+# starting from a known substring within the string and of m length, say 2:
+select s[ix:ix+(2-1)] from (select s, position('五六' in s) as ix from s());
+
+# For clarity we'll use DuckDB's 'list' output mode:
+.mode list