我有一张表，其中一个字段在纪元时间记录timestamp，并且我有一些查询需要使用“时间”范围返回结果。
例如
where timestamp >= 1512000000 and timestamp <=1513000000
我为timestamp设置了索引，但是查询结果花费的时间很长。
解释查询计划：
SEARCH TABLE data USING INDEX timestamp_idx (timestamp>? AND timestamp<?)
我已经阅读了一些有关树结构的文章，但是对于如何在现有系统中实现它们却一无所知。
包括完整的EXPLAIN（已编辑）查询。比我想要的还要复杂
sqlite> explain select fielda , timestamp , fieldb from (select fielda , timestamp , fieldb from main.db ) where timestamp >= a and timestamp <= b and fieldb in (x , x , x , x , x , x ) limit 0, -1;
addr opcode p1 p2 p3 p4 p5 comment
---- ------------- ---- ---- ---- ------------- -- -------------
0 Init 0 46 0 00 Start at 46
1 Integer -1 1 0 00 r[1]=-1; LIMIT counter
2 Integer 20 2 0 00 r[2]=20
3 MustBeInt 2 0 0 00 OFFSET counter
4 OffsetLimit 1 3 2 00 if r[1]>0 then r[3]=r[1]+max(0,r[2]) else r[3]=(-1); LIMIT+OFFSET
5 OpenRead 1 2 0 18 00 root=2 iDb=0; db
6 OpenRead 2 4 0 k(2,,) 02 root=4 iDb=0; fieldb_idx
7 Once 0 27 0 00
8 OpenEphemeral 4 1 0 k(1,B) 00 nColumn=1
9 Integer 103 5 0 00 r[5]=103
10 MakeRecord 5 1 6 D 00 r[6]=mkrec(r[5])
11 IdxInsert 4 6 5 1 00 key=r[6]
12 Integer 108 5 0 00 r[5]=108
13 MakeRecord 5 1 6 D 00 r[6]=mkrec(r[5])
14 IdxInsert 4 6 5 1 00 key=r[6]
15 Integer 104 5 0 00 r[5]=104
16 MakeRecord 5 1 6 D 00 r[6]=mkrec(r[5])
17 IdxInsert 4 6 5 1 00 key=r[6]
18 Integer 109 5 0 00 r[5]=109
19 MakeRecord 5 1 6 D 00 r[6]=mkrec(r[5])
20 IdxInsert 4 6 5 1 00 key=r[6]
21 Integer 105 5 0 00 r[5]=105
22 MakeRecord 5 1 6 D 00 r[6]=mkrec(r[5])
23 IdxInsert 4 6 5 1 00 key=r[6]
24 Integer 110 5 0 00 r[5]=110
25 MakeRecord 5 1 6 D 00 r[6]=mkrec(r[5])
26 IdxInsert 4 6 5 1 00 key=r[6]
27 Rewind 4 45 0 00
28 Column 4 0 4 00 r[4]=
29 IsNull 4 44 0 00 if r[4]==NULL goto 44
30 Affinity 4 1 0 D 00 affinity(r[4])
31 SeekGE 2 44 4 1 00 key=r[4]
32 IdxGT 2 44 4 1 00 key=r[4]
33 DeferredSeek 2 0 1 00 Move 1 to 2.rowid if needed
34 Column 1 0 6 00 r[6]=db.timestamp
35 Lt 7 43 6 (BINARY) 54 if r[6]<r[7] goto 43
36 Gt 8 43 6 (BINARY) 54 if r[6]>r[8] goto 43
37 IfPos 2 43 1 00 if r[2]>0 then r[2]-=1, goto 43; OFFSET
38 Column 1 17 9 00 r[9]=db.fielda
39 Copy 6 10 0 00 r[10]=r[6]
40 Column 2 0 11 00 r[11]=db.fieldb
41 ResultRow 9 3 0 00 output=r[9..11]
42 DecrJumpZero 1 45 0 00 if (--r[1])==0 goto 45
43 Next 2 32 0 00
44 NextIfOpen 4 28 0 00
45 Halt 0 0 0 00
46 Transaction 0 0 3 0 01 usesStmtJournal=0
47 Integer 1519862400 7 0 00 r[7]=1519862400
48 Integer 1522540800 8 0 00 r[8]=1522540800
49 Goto 0 1 0 00