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The `system.unicode` table is a virtual table that provides information about Unicode characters and their properties(<https://unicode-org.github.io/icu/userguide/strings/properties.html>). This table is generated on-the-fly.

Columns

Note

The property names of Unicode code points in ICU documents are converted to snake case.

- `code_point` ([String](/docs/sql-reference/data-types/string)) — The UTF-8 representation of the code point.
- `code_point_value` ([Int32](/docs/sql-reference/data-types/int-uint)) — The numeric value of the code point.
- `notation` ([String](/docs/sql-reference/data-types/string)) — The Unicode notation of the code point.
- Binary Properties ([UInt8](/docs/sql-reference/data-types/int-uint)) - The binary properties of the code point.
  - `alphabetic`, `ascii_hex_digit`, `case_ignorable`...
- Enumerated Properties ([Int32](/docs/sql-reference/data-types/int-uint)) - The enumerated properties of the code point.
  - `bidi_class`, `bidi_paired_bracket_type`, `block`...
- String Properties ([String](/docs/sql-reference/data-types/string)) - The string properties(ASCII String or Unicode String or code point) of the code point
  - `case_folding`, `decomposition_mapping`, `name`...

Note

Mapping is somewhat special, see the icu documentation. For example, simple\_uppercase\_mapping and uppercase\_mapping are not exactly the same. But no language-specific mappings are implemented (e.g. Turkish the upper case of i is "İ" (U+0130))

- `numeric_value` ([Float64](/docs/sql-reference/data-types/float)) - The numeric value of the code point.
- `script_extensions` ([Array(LowCardinality(String))](/docs/sql-reference/data-types/array)) - The script extensions of the code point.
- `identifier_type` ([Array(LowCardinality(String))](/docs/sql-reference/data-types/array)) - The identifier type of the code point.
- `general_category_mask` ([Int32](/docs/sql-reference/data-types/int-uint)) - The general category mask of the code point.

**Example**

```
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  │
   └────────────┴──────────────────┴──────────┘
```

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