Recursive_table_next, ",", recursive_table_union, Set recursive_table_tmp = concat(recursive_table, "_tmp") ĬONCAT("DROP TEMPORARY TABLE IF EXISTS ", recursive_table, ",", Set recursive_table_union = concat(recursive_table, "_union") Set recursive_table_next = concat(recursive_table, "_next") # to your recursive_table, to speed up initial/recursive/final SELECTs example:ĭeclare show_progress int default 0 # set to 1 to trace/debug executionĭeclare recursive_table_next varchar(120) ĭeclare recursive_table_union varchar(120) ĭeclare recursive_table_tmp varchar(120) Max_recursion int unsigned, # safety against infinite loop, use 0 for defaultĬreate_table_options varchar(65530) # you can add CREATE-TABLE-time options Recursive_SELECT varchar(65530), # recursive memberįinal_SELECT varchar(65530), # final SELECT on UNION result
Initial_SELECT varchar(65530), # seed a.k.a. Recursive_table varchar(100), # name of recursive table # It would be possible to write a SP creating multiple recursive tables. # 6) run final select, send relult to client # else swap T0 and T1 (renaming) and empty T1 # run recursive_SELECT based on T0 and put result into table T1, # 2) We have a union table U, initially empty. # "recursive_table"), we fill it with result of initial_SELECT. # 1) we have an initial table T0 (actual name is an argument
# CALL WITH_EMULATOR(recursive_table, initial_SELECT, recursive_SELECT,
#Hackerrank mysql version code
SELECT M.ID, M.NAME, M.MANAGER_ID, SUM(1+E.REPORTS) AS REPORTSįROM EMPLOYEES M JOIN EMPLOYEES_EXTENDED E ON M.ID=E.MANAGER_IDĪnd this is the code or the stored procedure # Usage: the standard syntax: WHERE ID NOT IN (SELECT MANAGER_ID FROM EMPLOYEES WHERE MANAGER_ID IS NOT NULL) SELECT ID, NAME, MANAGER_ID, 0 AS REPORTS SELECT D1.YEAR, (CASE WHEN D1.S>D2.S THEN 'INCREASE' ELSE 'DECREASE' END) AS TRENDĢ) Recursive queries can be done with a stored procedure that makes the call similar to a recursive with query. Really good explanation on how these work to do a similar query as SQL WITH.ġ) Use WITH so you don't have to perform the same sub query multiple times CREATE VIEW D AS (SELECT YEAR, SUM(SALES) AS S FROM T1 GROUP BY YEAR) The post lays out ways of emulating the 2 uses of SQL WITH. I followed the link shared by lisachenko and found another link to this blog:
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