SYSSCHEMAS is a view, located in librqary QSYS2 (on v6r1) with the following definition:
CREATE VIEW SYSSCHEMAS ( SCHEMA_NAME FOR COLUMN NAME, SCHEMA_OWN
ER FOR COLUMN OWNER, SCHEMA_CREATOR FOR COLUMN CREATOR, CREATI
ON_TIMESTAMP FOR COLUMN "TIMESTAMP", SCHEMA_SIZE FOR COLUMN SIZE
, SCHEMA_TEXT FOR COLUMN LABEL, SYSTEM_SCHEMA_NAME FOR COLUMN SY
S_NAME) AS SELECT COALESCE(P.OBJLONGNAME,''), COALESCE(VARCHAR(STRI
P(P.OBJOWNER,TRAILING),128),''), COALESCE(VARCHAR(STRIP(P.OBJDEFINE
R,TRAILING),128),''), COALESCE(P.OBJCREATED,'0001-01-01-00.00.00'),
COALESCE(OBJSIZE,0), CAST(TRIM(OBJTEXT) AS VARCHAR(50)), CAST(COALE
SCE(OBJNAME,'') AS CHAR(10)) FROM TABLE (QSYS2.OBJECT_STATISTICS('QS
YS ','LIB ')) AS P