pgsql similar to
时间: 2024-03-17 20:38:28 浏览: 24
PgSQL的"similar to"是一种用于模式匹配的操作符。它可以在查询中使用,用于比较字符串与模式之间的相似性。
"similar to"操作符使用正则表达式来定义模式,并将其应用于字符串。它支持一些特殊字符和通配符,如%(匹配任意字符序列)和_(匹配任意单个字符)。
下面是一些示例:
1. 查找以字母"a"开头的字符串:
SELECT * FROM table_name WHERE column_name SIMILAR TO 'a%';
2. 查找以字母"a"结尾的字符串:
SELECT * FROM table_name WHERE column_name SIMILAR TO '%a';
3. 查找包含两个连续的字母"a"的字符串:
SELECT * FROM table_name WHERE column_name SIMILAR TO '%a%a%';
4. 查找以字母"a"开头和以字母"b"结尾的字符串:
SELECT * FROM table_name WHERE column_name SIMILAR TO 'a%b';
请注意,"similar to"操作符对大小写敏感。如果需要进行大小写不敏感的匹配,可以使用ILIKE操作符。
相关问题
pgsql todate
To convert a PostgreSQL date to a specific format, you can use the `to_char` function. Here's an example:
```sql
SELECT to_char(your_date_column, 'YYYY-MM-DD') AS formatted_date
FROM your_table;
```
Replace `your_date_column` with the column name that contains the date, and `your_table` with the table name.
You can customize the format according to your needs. In the example above, `'YYYY-MM-DD'` represents the year, month, and day in the format of four digits for the year, two digits for the month, and two digits for the day. You can refer to the PostgreSQL documentation for more format options: https://www.postgresql.org/docs/current/functions-formatting.html
pgSQL to_date
在pgSQL中,to_date函数用于将字符串转换为日期。然而,该函数仅转换年月日部分,并且无论在函数中指定的日期格式如何,都只会转换年月日。例如,使用to_date函数转换字符串'2019-01-15 18:33:41',结果仅为日期部分,即'2019-01-15'。<span class="em">1</span><span class="em">2</span><span class="em">3</span>
#### 引用[.reference_title]
- *1* *2* [postgresql 踩坑系列 关于to_date()](https://blog.csdn.net/qq_36273946/article/details/86546350)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v92^chatsearchT3_1"}}] [.reference_item style="max-width: 50%"]
- *3* [PGSQL to_date转换年月日时分秒发现格式不对](https://blog.csdn.net/a984171281/article/details/120329794)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v92^chatsearchT3_1"}}] [.reference_item style="max-width: 50%"]
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