Solution to renaming MySQL table fields containing hyphens
Including hyphens directly in MySQL table field names is not allowed. This is because MySQL uses dot notation to refer to table columns, and hyphens are not allowed in dot notation.
However, there are two ways to work around this limitation:
Use delimiter
You can use delimiters such as backticks (`) or double quotes (") to enclose field names that contain special characters. For example:
ALTER TABLE my_table CHANGE COLUMN `product` `ds-product` VARCHAR(255);
In this example, the field name ds-product
is enclosed in backticks, allowing it to contain hyphens.
Use ANSI_QUOTES SQL mode
Another option is to enable ANSI_QUOTES SQL mode, which allows the use of double quotes as delimiters for identifiers. When this mode is enabled, fields can be renamed using the following syntax:
SET SQL_MODE = ANSI_QUOTES; ALTER TABLE my_table CHANGE COLUMN "product" "ds-product" VARCHAR(255);
Note that you need to set the ANSI_QUOTES mode before renaming fields.
After using any of the above methods, you can rename the field and use it in queries without encountering "unknown column" errors.
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