How to replace text in a field in sql
There are two ways to replace field text in SQL: 1. REPLACE() function: replace the specified substring in the string; 2. UPDATE statement: use the CASE statement to replace field text based on conditions.
Two methods to replace text in a field in SQL
In SQL, you can use to replace text in a field Two methods: REPLACE() function and UPDATE statement.
1. REPLACE() function
The REPLACE() function is a function used in SQL to replace a specific substring in a string. The syntax is as follows:
REPLACE(string, search_string, replace_string)
Where:
- string: The string expression from which the substring is to be replaced.
- search_string: The substring to be replaced.
- replace_string: New string used to replace search_string.
Example:
Replace "New York" in the "City" column of the table "Customers" with "New City":
UPDATE Customers SET City = REPLACE(City, 'New York', 'New City');
2. UPDATE statement
The UPDATE statement can also be used to replace Chinese characters in fields. Its syntax is as follows:
UPDATE table_name
SET column_name = CASE
WHEN current_value = search_string THEN replace_string
ELSE current_value
END
WHERE condition;where:
- table_name: The name of the table to be updated.
- column_name: The column name to replace the text.
- current_value: The current value of the field.
- search_string: The substring to be replaced.
- replace_string: New string used to replace search_string.
- condition: Specifies the condition for which rows to update.
Example:
Replace "2023-03-01" in the "OrderDate" column in the table "Orders" with "2023-04-01":
UPDATE Orders
SET OrderDate = CASE
WHEN OrderDate = '2023-03-01' THEN '2023-04-01'
ELSE OrderDate
END
WHERE OrderDate = '2023-03-01';The above is the detailed content of How to replace text in a field in sql. For more information, please follow other related articles on the PHP Chinese website!
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