Db2 Developer-C 11.1

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WITH 
 i(init) AS (VALUES('db2')),
 c(cd) AS (VALUES(2018)),
 n(num) AS (VALUES(53)),
 cte AS
    (SELECT 'mysql' AS mytype,45.2707 AS mynum,'LlB' AS mychar,'2018-06-18' AS mydate FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',91.5861,'d7I','2015-05-10' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sql server',77.9822,'4Wn','2017-01-29' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',85.5323,'sqz','2016-01-05' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2', 5.8967,'fS1','2018-07-24' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',54.8832,'1hp','2015-11-01' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sqlite',63.0003,'vxS','2016-02-26' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sql server',68.3834,'wB8','2015-02-16' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sql server',30.7427,'CD3','2016-06-08' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sql server',98.9217,'SXz','2015-09-29' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',29.7813,'h1D','2017-04-30' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',97.0466,'fjD','2018-02-08' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',30.0664,'Snh','2015-07-06' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',27.6271,'TSs','2016-10-21' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',66.1275,'XT8','2018-11-17' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sqlite',83.3873,'Tea','2018-03-20' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',32.3265,'yU1','2018-08-01' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql', 1.8472,'EH5','2017-10-27' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',17.9318,'BmM','2018-09-21' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',41.1535,'14M','2017-04-30' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sql server', 4.6209,'5RJ','2017-01-26' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',81.6313,'RPQ','2018-11-22' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'postgres',47.1262,'XNF','2015-08-01' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',55.6534,'AER','2017-05-07' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',38.5642,'0aW','2015-03-05' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'postgres', 7.2746,'Sef','2016-01-09' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'oracle',97.9196,'niw','2017-12-14' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',89.7996,'38C','2015-07-06' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sql server',96.6379,'oCx','2016-06-10' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'oracle',80.1203,'jeg','2016-10-10' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',98.8097,'FdZ','2018-09-15' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sqlite',54.6743,'Eqc','2016-09-22' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'postgres',70.1591,'6Uy','2016-04-01' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sqlite',73.2635,'wA9','2015-03-04' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',33.6310,'8db','2015-12-30' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql', 4.7905,'Wx0','2015-02-25' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'postgres',99.2243,'DC4','2017-05-26' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'oracle',51.8137,'k2H','2017-03-23' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'oracle',41.0709,'IYL','2017-06-13' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sql server',22.0057,'84M','2017-09-09' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',77.6216,'Kg1','2015-02-19' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'oracle',12.9395,'jJ4','2017-12-11' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'db2',52.6506,'r3R','2018-01-05' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sql server',24.0093,'5U1','2016-08-27' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',31.9740,'b5I','2016-04-02' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',93.6116,'aJ8','2016-09-06' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',18.8313,'XBh','2015-03-12' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sqlite',19.3405,'iFF','2016-06-07' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sqlite',38.5261,'dPj','2017-04-19' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'sqlite',70.0422,'I4m','2015-05-02' FROM SYSIBM.SYSDUMMY1 UNION ALL
     SELECT 'mysql',51.4506,'LlB','2018-06-18' FROM SYSIBM.SYSDUMMY1
)

SELECT *
FROM cte, i, c, n
WHERE cte.mytype = NVL(i.init, cte.mytype)
AND YEAR(CAST(cte.mydate AS date)) = NVL(c.cd, YEAR(CAST(cte.mydate AS date)))
AND ROUND(cte.mynum, 0) = NVL(n.num, ROUND(cte.mynum, 0));

MYTYPE	MYNUM	MYCHAR	MYDATE	INIT	CD	NUM
db2	52.6506	r3R	2018-01-05	db2	2018	53