mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-21 15:12:02 +00:00
Merge pull request #62109 from Blargian/document_hasXYZ
Document hasXYZ
This commit is contained in:
commit
38254cf52d
@ -543,12 +543,64 @@ You can get similar result by using the [ternary operator](../../sql-reference/f
|
||||
|
||||
Returns 1 if the Float32 and Float64 argument is NaN, otherwise this function 0.
|
||||
|
||||
## hasColumnInTable(\[‘hostname’\[, ‘username’\[, ‘password’\]\],\] ‘database’, ‘table’, ‘column’)
|
||||
## hasColumnInTable
|
||||
|
||||
Given the database name, the table name, and the column name as constant strings, returns 1 if the given column exists, otherwise 0.
|
||||
|
||||
**Syntax**
|
||||
|
||||
```sql
|
||||
hasColumnInTable(\[‘hostname’\[, ‘username’\[, ‘password’\]\],\] ‘database’, ‘table’, ‘column’)
|
||||
```
|
||||
|
||||
**Parameters**
|
||||
|
||||
- `database` : name of the database. [String literal](../syntax#syntax-string-literal)
|
||||
- `table` : name of the table. [String literal](../syntax#syntax-string-literal)
|
||||
- `column` : name of the column. [String literal](../syntax#syntax-string-literal)
|
||||
- `hostname` : remote server name to perform the check on. [String literal](../syntax#syntax-string-literal)
|
||||
- `username` : username for remote server. [String literal](../syntax#syntax-string-literal)
|
||||
- `password` : password for remote server. [String literal](../syntax#syntax-string-literal)
|
||||
|
||||
**Returned value**
|
||||
|
||||
- `1` if the given column exists.
|
||||
- `0`, otherwise.
|
||||
|
||||
**Implementation details**
|
||||
|
||||
Given the database name, the table name, and the column name as constant strings, returns 1 if the given column exists, otherwise 0. If parameter `hostname` is given, the check is performed on a remote server.
|
||||
If the table does not exist, an exception is thrown.
|
||||
For elements in a nested data structure, the function checks for the existence of a column. For the nested data structure itself, the function returns 0.
|
||||
|
||||
**Example**
|
||||
|
||||
Query:
|
||||
|
||||
```sql
|
||||
SELECT hasColumnInTable('system','metrics','metric')
|
||||
```
|
||||
|
||||
```response
|
||||
1
|
||||
```
|
||||
|
||||
```sql
|
||||
SELECT hasColumnInTable('system','metrics','non-existing_column')
|
||||
```
|
||||
|
||||
```response
|
||||
0
|
||||
```
|
||||
|
||||
## hasThreadFuzzer
|
||||
|
||||
Returns whether Thread Fuzzer is effective. It can be used in tests to prevent runs from being too long.
|
||||
|
||||
**Syntax**
|
||||
|
||||
```sql
|
||||
hasThreadFuzzer();
|
||||
```
|
||||
|
||||
## bar
|
||||
|
||||
Builds a bar chart.
|
||||
|
@ -967,8 +967,10 @@ Type: `UInt8`.
|
||||
|
||||
**Examples**
|
||||
|
||||
Query:
|
||||
|
||||
``` sql
|
||||
SELECT hasSubsequence('garbage', 'arg') ;
|
||||
SELECT hasSubsequence('garbage', 'arg');
|
||||
```
|
||||
|
||||
Result:
|
||||
@ -983,10 +985,263 @@ Result:
|
||||
|
||||
Like [hasSubsequence](#hasSubsequence) but searches case-insensitively.
|
||||
|
||||
**Syntax**
|
||||
|
||||
``` sql
|
||||
hasSubsequenceCaseInsensitive(haystack, needle)
|
||||
```
|
||||
|
||||
**Arguments**
|
||||
|
||||
- `haystack` — String in which the search is performed. [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
- `needle` — Subsequence to be searched. [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
|
||||
**Returned values**
|
||||
|
||||
- 1, if needle is a subsequence of haystack.
|
||||
- 0, otherwise.
|
||||
|
||||
Type: `UInt8`.
|
||||
|
||||
**Examples**
|
||||
|
||||
Query:
|
||||
|
||||
``` sql
|
||||
SELECT hasSubsequenceCaseInsensitive('garbage', 'ARG');
|
||||
```
|
||||
|
||||
Result:
|
||||
|
||||
``` text
|
||||
┌─hasSubsequenceCaseInsensitive('garbage', 'ARG')─┐
|
||||
│ 1 │
|
||||
└─────────────────────────────────────────────────┘
|
||||
```
|
||||
|
||||
## hasSubsequenceUTF8
|
||||
|
||||
Like [hasSubsequence](#hasSubsequence) but assumes `haystack` and `needle` are UTF-8 encoded strings.
|
||||
|
||||
**Syntax**
|
||||
|
||||
``` sql
|
||||
hasSubsequenceUTF8(haystack, needle)
|
||||
```
|
||||
|
||||
**Arguments**
|
||||
|
||||
- `haystack` — String in which the search is performed. UTF-8 encoded [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
- `needle` — Subsequence to be searched. UTF-8 encoded [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
|
||||
**Returned values**
|
||||
|
||||
- 1, if needle is a subsequence of haystack.
|
||||
- 0, otherwise.
|
||||
|
||||
Type: `UInt8`.
|
||||
|
||||
Query:
|
||||
|
||||
**Examples**
|
||||
|
||||
``` sql
|
||||
select hasSubsequenceUTF8('ClickHouse - столбцовая система управления базами данных', 'система');
|
||||
```
|
||||
|
||||
Result:
|
||||
|
||||
``` text
|
||||
┌─hasSubsequenceUTF8('ClickHouse - столбцовая система управления базами данных', 'система')─┐
|
||||
│ 1 │
|
||||
└───────────────────────────────────────────────────────────────────────────────────────────┘
|
||||
```
|
||||
|
||||
## hasSubsequenceCaseInsensitiveUTF8
|
||||
|
||||
Like [hasSubsequenceUTF8](#hasSubsequenceUTF8) but searches case-insensitively.
|
||||
|
||||
**Syntax**
|
||||
|
||||
``` sql
|
||||
hasSubsequenceCaseInsensitiveUTF8(haystack, needle)
|
||||
```
|
||||
|
||||
**Arguments**
|
||||
|
||||
- `haystack` — String in which the search is performed. UTF-8 encoded [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
- `needle` — Subsequence to be searched. UTF-8 encoded [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
|
||||
**Returned values**
|
||||
|
||||
- 1, if needle is a subsequence of haystack.
|
||||
- 0, otherwise.
|
||||
|
||||
Type: `UInt8`.
|
||||
|
||||
**Examples**
|
||||
|
||||
Query:
|
||||
|
||||
``` sql
|
||||
select hasSubsequenceCaseInsensitiveUTF8('ClickHouse - столбцовая система управления базами данных', 'СИСТЕМА');
|
||||
```
|
||||
|
||||
Result:
|
||||
|
||||
``` text
|
||||
┌─hasSubsequenceCaseInsensitiveUTF8('ClickHouse - столбцовая система управления базами данных', 'СИСТЕМА')─┐
|
||||
│ 1 │
|
||||
└──────────────────────────────────────────────────────────────────────────────────────────────────────────┘
|
||||
```
|
||||
|
||||
## hasToken
|
||||
|
||||
Returns 1 if a given token is present in a haystack, or 0 otherwise.
|
||||
|
||||
**Syntax**
|
||||
|
||||
```sql
|
||||
hasToken(haystack, token)
|
||||
```
|
||||
|
||||
**Parameters**
|
||||
|
||||
- `haystack`: String in which the search is performed. [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
- `token`: Maximal length substring between two non alphanumeric ASCII characters (or boundaries of haystack).
|
||||
|
||||
**Returned value**
|
||||
|
||||
- 1, if the token is present in the haystack.
|
||||
- 0, if the token is not present.
|
||||
|
||||
**Implementation details**
|
||||
|
||||
Token must be a constant string. Supported by tokenbf_v1 index specialization.
|
||||
|
||||
**Example**
|
||||
|
||||
Query:
|
||||
|
||||
```sql
|
||||
SELECT hasToken('Hello World','Hello');
|
||||
```
|
||||
|
||||
```response
|
||||
1
|
||||
```
|
||||
|
||||
## hasTokenOrNull
|
||||
|
||||
Returns 1 if a given token is present, 0 if not present, and null if the token is ill-formed.
|
||||
|
||||
**Syntax**
|
||||
|
||||
```sql
|
||||
hasTokenOrNull(haystack, token)
|
||||
```
|
||||
|
||||
**Parameters**
|
||||
|
||||
- `haystack`: String in which the search is performed. [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
- `token`: Maximal length substring between two non alphanumeric ASCII characters (or boundaries of haystack).
|
||||
|
||||
**Returned value**
|
||||
|
||||
- 1, if the token is present in the haystack.
|
||||
- 0, if the token is not present in the haystack.
|
||||
- null, if the token is ill-formed.
|
||||
|
||||
**Implementation details**
|
||||
|
||||
Token must be a constant string. Supported by tokenbf_v1 index specialization.
|
||||
|
||||
**Example**
|
||||
|
||||
Where `hasToken` would throw an error for an ill-formed token, `hasTokenOrNull` returns `null` for an ill-formed token.
|
||||
|
||||
Query:
|
||||
|
||||
```sql
|
||||
SELECT hasTokenOrNull('Hello World','Hello,World');
|
||||
```
|
||||
|
||||
```response
|
||||
null
|
||||
```
|
||||
|
||||
## hasTokenCaseInsensitive
|
||||
|
||||
Returns 1 if a given token is present in a haystack, 0 otherwise. Ignores case.
|
||||
|
||||
**Syntax**
|
||||
|
||||
```sql
|
||||
hasTokenCaseInsensitive(haystack, token)
|
||||
```
|
||||
|
||||
**Parameters**
|
||||
|
||||
- `haystack`: String in which the search is performed. [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
- `token`: Maximal length substring between two non alphanumeric ASCII characters (or boundaries of haystack).
|
||||
|
||||
**Returned value**
|
||||
|
||||
- 1, if the token is present in the haystack.
|
||||
- 0, otherwise.
|
||||
|
||||
**Implementation details**
|
||||
|
||||
Token must be a constant string. Supported by tokenbf_v1 index specialization.
|
||||
|
||||
**Example**
|
||||
|
||||
Query:
|
||||
|
||||
```sql
|
||||
SELECT hasTokenCaseInsensitive('Hello World','hello');
|
||||
```
|
||||
|
||||
```response
|
||||
1
|
||||
```
|
||||
|
||||
## hasTokenCaseInsensitiveOrNull
|
||||
|
||||
Returns 1 if a given token is present in a haystack, 0 otherwise. Ignores case and returns null if the token is ill-formed.
|
||||
|
||||
**Syntax**
|
||||
|
||||
```sql
|
||||
hasTokenCaseInsensitiveOrNull(haystack, token)
|
||||
```
|
||||
|
||||
**Parameters**
|
||||
|
||||
- `haystack`: String in which the search is performed. [String](../../sql-reference/syntax.md#syntax-string-literal).
|
||||
- `token`: Maximal length substring between two non alphanumeric ASCII characters (or boundaries of haystack).
|
||||
|
||||
**Returned value**
|
||||
|
||||
- 1, if the token is present in the haystack.
|
||||
- 0, if token is not present.
|
||||
- null, if the token is ill-formed.
|
||||
|
||||
**Implementation details**
|
||||
|
||||
Token must be a constant string. Supported by tokenbf_v1 index specialization.
|
||||
|
||||
**Example**
|
||||
|
||||
|
||||
Where `hasTokenCaseInsensitive` would throw an error for an ill-formed token, `hasTokenCaseInsensitiveOrNull` returns `null` for an ill-formed token.
|
||||
|
||||
Query:
|
||||
|
||||
```sql
|
||||
SELECT hasTokenCaseInsensitiveOrNull('Hello World','hello,world');
|
||||
```
|
||||
|
||||
```response
|
||||
null
|
||||
```
|
@ -1680,6 +1680,7 @@ hasSubsequenceCaseInsensitiveUTF
|
||||
hasSubsequenceUTF
|
||||
hasSubstr
|
||||
hasToken
|
||||
hasThreadFuzzer
|
||||
hasTokenCaseInsensitive
|
||||
hasTokenCaseInsensitiveOrNull
|
||||
hasTokenOrNull
|
||||
|
Loading…
Reference in New Issue
Block a user