A locking read, an UPDATE, or a DELETE generally set record locks on every index record that is scanned in the processing of the SQL statement.
index record is often seen in Mysql documents. Is it "index and record" or is there any other specific reference?
how to translate the above sentence?
Thank you
index record can be understood to mean that every row of the index row, MySQL B tree index is the index key value + primary key;
locks reads, and update,delete usually locks the index rows it scans. For example, tab has a br b column, a column is the primary key, b column has an index, and the data is as follows:
ab
1 5
26
3 7
when issuing SQL:update tab set bread10 where bread5, then MySQL will lock this row, and this row lock is actually achieved by locking the index key of b column index bend5.
Lock read, update, or delete usually sets a record lock on each index record, which is scanned during the processing of the SQL statement declaration.
index record-an index record is an index.
there are many attributives in the above sentence, you can repeat some names when it is difficult to express in Chinese, for example, I have repeated the index record. Of course, my translation is not a standard answer, it is handled according to personal understanding, for reference only.
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