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EXPLAIN [(option [,...])] statement

EXPLAIN [ANALYZE] [VERBOSE] statement

The options that can be followed by explain are:

ANALYZE [boolean]-execute statement to get real run time and statistics.

VERBOSE [boolean]-- outputs details such as columns, schema,trigger, etc. Off by default.

COSTS [boolean]-outputs the cost value calculated based on the cost factor, which is turned on by default. (divided into the cost before the node outputs the first line and the cost of outputting all rows.)

BUFFERS [boolean]-- outputs the information of this QUERY shared/local/TEMP blocks. The number of shared blocks hit, read, dirtied, and written, the

Number of local blocks hit, read, dirtied, and written, and the number of temp blocks read and written.

Including hit / miss read data blocks, the resulting dirty data blocks, write out how many dirty data blocks before QUERY starts. (you need to open the analyze, TEXT mode

Type output only non-zero items, "count includes the count of all child nodes.")

TIMING [boolean]-outputs the real time cost of each node. The total time does not include network cost, parser,rewriter,planer cost, (need to open analyze)

FORMAT {TEXT | XML | JSON | YAML}-output format, default TEXT.

Note: for the use of analyze, the evaluated SQL is actually executed, and if the DML is performed, it can be used in the transaction and rolled back:

BEGIN

EXPLAIN ANALYZE QUERY

ROLLBACK

FORMAT {TEXT | XML | JSON | YAML}-output format, default TEXT.

Explain (analyze,verbose,buffers,costs,timing) select id1 from t_info10 where id1

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