Note: Use BTREE to comindex ASC/DESC of each field to optimize order by query efficiency. btreeascThe tbl_direct_pos_201506 table has 1.9 million data, DDL:
Create table 'tbl _ direct_pos_201506 '('acq _ ins_code' char (13) not null default
Li Wu:Heng Learn to think together, honouring teachers save Thanksgiving. Leaf See root three return to one, rivers the same oneness.Meekness Conscience Lord, willing to do without regrets to the most bitter. Reading exercises to keep the body and
The MySQL order BY keyword is used to classify the data in the record.
MySQL ORDER BY keyword classified by keyword
The ORDER BY keyword is used to classify the data in a record.
MySQL ORDER BY syntax
The code is as follows
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Note: Use the BTREE compound to index the ASC/DESC of each field to optimize the orderby query efficiency.The tbl_direct_pos_201506 table has 1.9 million data, DDL:
Create table 'tbl _ direct_pos_201506 '('acq _ ins_code' char (13) not null default '
In some cases, MySQL can use an index to satisfy the order by clause without additional sorting. The where condition and order by condition use the same index, and the order by order is the same as the index order, and the order by field is both
The main purpose of this article is to demonstrate how
LookMySQL joins. by "look at" I mean how to see through MySQL's eyes, so-to-speak. this task is fundamentally different from the rather straight-forward tasks of how to do joins or how to index
MySQL Order By Principle and Optimization
1 IntroductionFor business (MySQL) DBAs or business developers, order by is a common business function that sorts the results based on specified fields to meet front-end display requirements. However,
Often forget MySQL in ascending and descending with what characters, now make a note: ascending asc, descending desc, for example, the following is a time descending call column of the article, also is the column of the latest
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