cassandra——可以预料的查询，如果你的查询条件有一个是根据索引查询，那其它非索引非主键字段，可以通过加一个ALLOW FILTERING来过滤实现

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CREATE TABLE test(
a INT,
b INT,
c INT,
d INT,
e INT,
m INT,
PRIMARY KEY(a,b,c));

CREATE INDEX ON test(c);
CREATE INDEX ON test(e);

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CREATE INDEX ON test(a) X

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SELECT * FROM test WHERE e=1; //是可以
SELECT * FROM test WHERE e>1; //就不行了。

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SELECT * FROM test WHERE e=1 AND m>2 ALLOW FILTERING;

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SELECT * FROM test WHERE a=1 ORDER BY b DESC;
SELECT * FROM test WHERE a=1 ORDER BY b DESC, c DESC;
SELECT * FROM test WHERE a=1 ORDER BY b ASC;
SELECT * FROM test WHERE a=1 ORDER BY b ASC, c ASC;

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SELECT * FROM test ORDER BY b DESC; //没有第一主键 不行
SELECT * FROM test WHERE a=1 ORDER BY c DESC; //必须以第二主键开始排序
SELECT * FROM test WHERE a=1 ORDER BY b DESC, c ASC; //不是相同的排序。
SELECT * FROM test WHERE e=1 ORDER BY b DESC; //不能有索引。

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CREATE TABLE test(
a INT,
b INT,
c INT,
d INT,
e INT,
m INT,
PRIMARY KEY(a,b,c))
WITH CLUSTERING ORDER BY (b DESC, c ASC);