replace a Backslash
You need to mask a backslash in your source, and for regex, you need to mask it again, so for every backslash you need two, which ends in 4.
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select GROUP_CONCAT(CONCAT(COLUMN_NAME)) from INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = "facturelist" AND TABLE_SCHEMA = "em" ORDER BY ORDINAL_POSITION
