Schrödinger's MySQL Table: A Tale of Existence and Nonexistence
Encountering a paradox where MySQL reports a table exists yet rejects its creation is a perplexing issue. This article aims to unravel the mystery behind this Schrödinger's table dilemma.
As described in the original inquiry, executing CREATE TABLE results in a "table already exists" error, while DROP TABLE returns "unknown table." This cosmic quandary stumps users, leaving them with an intangible table that cannot be created or deleted.
The culprit, in most cases, lies in the presence of orphaned table files. MySQL manages data in two types of files: .frm for table definition and .MYI and .MYD (MYISAM), or .ibd (InnoDB) for table data. When one of these files goes missing, the table becomes a half-formed phantom, leading to the inconsistency in MySQL's response.
To resolve this Schrödinger's table conundrum, manually locate and delete the orphaned file from the data directory. If using InnoDB, ensure both .frm and .ibd files exist, while MYISAM tables require a complete trio of .frm, .MYI, and .MYD files.
Once the orphaned file is removed, the paradox vanishes, and the table can be either created or dropped as expected. Thus, the elusive Schrödinger's table is resolved, demonstrating that in the realm of MySQL, existence and nonexistence can sometimes intertwine in perplexing ways.
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