说明
system.unicode 表是一个虚拟表，提供有关 Unicode 字符及其属性(https://unicode-org.github.io/icu/userguide/strings/properties.html)的信息。该表会动态生成。
来自 ICU 的 Unicode 码点属性名称会转换为 snake_case，并用作列名。
列
code_point(String) — 以 U+XXXX 表示的 Unicode 码点。code_point_value(Int32) — Unicode 码点的整数值。notation(String) — 字符表示法 (即码点的可视表示) 。
示例
SELECT * FROM system.unicode WHERE code_point = 'a' LIMIT 1;
Row 1:
──────
code_point: a
code_point_value: 97
notation: U+0061
alphabetic: 1
ascii_hex_digit: 1
bidi_control: 0
bidi_mirrored: 0
dash: 0
default_ignorable_code_point: 0
deprecated: 0
diacritic: 0
extender: 0
full_composition_exclusion: 0
grapheme_base: 1
grapheme_extend: 0
grapheme_link: 0
hex_digit: 1
hyphen: 0
id_continue: 1
id_start: 1
ideographic: 0
ids_binary_operator: 0
ids_trinary_operator: 0
join_control: 0
logical_order_exception: 0
lowercase: 1
math: 0
noncharacter_code_point: 0
quotation_mark: 0
radical: 0
soft_dotted: 0
terminal_punctuation: 0
unified_ideograph: 0
uppercase: 0
white_space: 0
xid_continue: 1
xid_start: 1
case_sensitive: 1
sentence_terminal: 0
variation_selector: 0
nfd_inert: 1
nfkd_inert: 1
nfc_inert: 0
nfkc_inert: 0
segment_starter: 1
pattern_syntax: 0
pattern_white_space: 0
alnum: 1
blank: 0
graph: 1
print: 1
xdigit: 1
cased: 1
case_ignorable: 0
changes_when_lowercased: 0
changes_when_uppercased: 1
changes_when_titlecased: 1
changes_when_casefolded: 0
changes_when_casemapped: 1
changes_when_nfkc_casefolded: 0
emoji: 0
emoji_presentation: 0
emoji_modifier: 0
emoji_modifier_base: 0
emoji_component: 0
regional_indicator: 0
prepended_concatenation_mark: 0
extended_pictographic: 0
basic_emoji: 0
emoji_keycap_sequence: 0
rgi_emoji_modifier_sequence: 0
rgi_emoji_flag_sequence: 0
rgi_emoji_tag_sequence: 0
rgi_emoji_zwj_sequence: 0
rgi_emoji: 0
ids_unary_operator: 0
id_compat_math_start: 0
id_compat_math_continue: 0
bidi_class: 0
block: 1
canonical_combining_class: 0
decomposition_type: 0
east_asian_width: 4
general_category: 2
joining_group: 0
joining_type: 0
line_break: 2
numeric_type: 0
script: 25
hangul_syllable_type: 0
nfd_quick_check: 1
nfkd_quick_check: 1
nfc_quick_check: 1
nfkc_quick_check: 1
lead_canonical_combining_class: 0
trail_canonical_combining_class: 0
grapheme_cluster_break: 0
sentence_break: 4
word_break: 1
bidi_paired_bracket_type: 0
indic_positional_category: 0
indic_syllabic_category: 0
vertical_orientation: 0
identifier_status: 1
general_category_mask: 4
numeric_value: 0
age: 1.1
bidi_mirroring_glyph: a
case_folding: a
lowercase_mapping: a
name: LATIN SMALL LETTER A
simple_case_folding: a
simple_lowercase_mapping: a
simple_titlecase_mapping: A
simple_uppercase_mapping: A
titlecase_mapping: A
uppercase_mapping: A
bidi_paired_bracket: a
script_extensions: ['Latin']
identifier_type: ['Recommended']
SELECT code_point, code_point_value, notation FROM system.unicode WHERE code_point = '😂';
┌─code_point─┬─code_point_value─┬─notation─┐
1. │ 😂 │ 128514 │ U+1F602 │
└────────────┴──────────────────┴──────────┘