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1
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With 1,000 rows:
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2
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3
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Without index:
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4
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5
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arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
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6
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QUERY PLAN
|
|
7
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--------------------------------------------------------
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8
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Seq Scan on links (cost=0.00..33.51 rows=3 width=224)
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9
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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10
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(2 rows)
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11
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|
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12
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arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
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13
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QUERY PLAN
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14
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---------------------------------------------------------
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15
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Seq Scan on links (cost=0.00..33.51 rows=14 width=224)
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16
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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17
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(2 rows)
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18
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19
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With index
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20
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21
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arvados_dev=> CREATE INDEX links_varchar_index_on_head_uuid ON links (head_uuid varchar_pattern_ops);
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22
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CREATE INDEX
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23
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arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
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24
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QUERY PLAN
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25
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--------------------------------------------------------
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26
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Seq Scan on links (cost=0.00..33.51 rows=3 width=224)
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27
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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28
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(2 rows)
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29
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|
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30
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arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
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31
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QUERY PLAN
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32
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----------------------------------------------------------------------------------------------------------------------
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33
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Bitmap Heap Scan on links (cost=4.38..23.84 rows=14 width=224)
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34
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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35
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-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.38 rows=13 width=0)
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36
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Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
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37
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(4 rows)
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38
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39
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40
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======
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41
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|
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42
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With 2,000 rows:
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43
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44
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Without index:
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45
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46
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arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
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47
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QUERY PLAN
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48
|
--------------------------------------------------------
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49
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Seq Scan on links (cost=0.00..51.06 rows=5 width=224)
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50
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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51
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(2 rows)
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52
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|
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53
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arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
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54
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QUERY PLAN
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55
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---------------------------------------------------------
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56
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Seq Scan on links (cost=0.00..51.06 rows=21 width=224)
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57
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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58
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(2 rows)
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59
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60
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With index:
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61
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62
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arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
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63
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QUERY PLAN
|
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64
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--------------------------------------------------------
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65
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Seq Scan on links (cost=0.00..51.06 rows=3 width=224)
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66
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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67
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(2 rows)
|
|
68
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|
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69
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
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70
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QUERY PLAN
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71
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----------------------------------------------------------------------------------------------------------------------
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72
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Bitmap Heap Scan on links (cost=4.38..29.20 rows=14 width=224)
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73
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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74
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-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.38 rows=13 width=0)
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75
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Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
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76
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(4 rows)
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77
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78
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79
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============
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80
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81
|
With 3,000 rows
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82
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83
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Without index:
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84
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|
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85
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arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
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86
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QUERY PLAN
|
|
87
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--------------------------------------------------------
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88
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Seq Scan on links (cost=0.00..78.39 rows=4 width=224)
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89
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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90
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(2 rows)
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91
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|
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92
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arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
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93
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QUERY PLAN
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|
94
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---------------------------------------------------------
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|
95
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Seq Scan on links (cost=0.00..81.51 rows=14 width=224)
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96
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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97
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(2 rows)
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98
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99
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|
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100
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With index:
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101
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102
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arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
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103
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QUERY PLAN
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104
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--------------------------------------------------------
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105
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Seq Scan on links (cost=0.00..81.51 rows=3 width=224)
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106
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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107
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(2 rows)
|
|
108
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|
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109
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
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|
110
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QUERY PLAN
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|
111
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----------------------------------------------------------------------------------------------------------------------
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112
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Bitmap Heap Scan on links (cost=4.38..33.75 rows=14 width=224)
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113
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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114
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-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.38 rows=13 width=0)
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115
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Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
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116
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(4 rows)
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117
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118
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119
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============
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120
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121
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With 4,000 rows
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122
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123
|
Without index:
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124
|
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125
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arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
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126
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QUERY PLAN
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127
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---------------------------------------------------------
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128
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Seq Scan on links (cost=0.00..129.51 rows=3 width=224)
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129
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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130
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(2 rows)
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|
131
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|
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132
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arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
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|
133
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QUERY PLAN
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|
134
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----------------------------------------------------------
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|
135
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Seq Scan on links (cost=0.00..129.51 rows=14 width=224)
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136
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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137
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(2 rows)
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138
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139
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140
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With index:
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141
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142
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
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143
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QUERY PLAN
|
|
144
|
---------------------------------------------------------
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145
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Seq Scan on links (cost=0.00..105.01 rows=3 width=224)
|
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146
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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147
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(2 rows)
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|
148
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|
|
149
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arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
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|
150
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QUERY PLAN
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|
151
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----------------------------------------------------------------------------------------------------------------------
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152
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Bitmap Heap Scan on links (cost=4.38..35.73 rows=14 width=224)
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153
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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|
154
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-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.38 rows=13 width=0)
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155
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Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
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156
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(4 rows)
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157
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|
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158
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|
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159
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==========
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160
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161
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With 5,000 rows:
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162
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163
|
Without index:
|
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164
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165
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
166
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QUERY PLAN
|
|
167
|
---------------------------------------------------------
|
|
168
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Seq Scan on links (cost=0.00..129.51 rows=3 width=224)
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169
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
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|
170
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(2 rows)
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|
171
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|
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172
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
173
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QUERY PLAN
|
|
174
|
----------------------------------------------------------
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|
175
|
Seq Scan on links (cost=0.00..129.51 rows=14 width=224)
|
|
176
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
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|
177
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(2 rows)
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178
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179
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|
180
|
With index:
|
|
181
|
|
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182
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
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183
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QUERY PLAN
|
|
184
|
---------------------------------------------------------
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185
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Seq Scan on links (cost=0.00..129.51 rows=3 width=224)
|
|
186
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Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
187
|
(2 rows)
|
|
188
|
|
|
189
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
190
|
QUERY PLAN
|
|
191
|
----------------------------------------------------------------------------------------------------------------------
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|
192
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Bitmap Heap Scan on links (cost=4.38..37.31 rows=14 width=224)
|
|
193
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Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
194
|
-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.38 rows=13 width=0)
|
|
195
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Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
|
|
196
|
(4 rows)
|
|
197
|
|
|
198
|
|
|
199
|
===========
|
|
200
|
|
|
201
|
with 10,000 rows:
|
|
202
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203
|
Without index:
|
|
204
|
|
|
205
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
206
|
QUERY PLAN
|
|
207
|
---------------------------------------------------------
|
|
208
|
Seq Scan on links (cost=0.00..248.01 rows=3 width=224)
|
|
209
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
210
|
(2 rows)
|
|
211
|
|
|
212
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
213
|
QUERY PLAN
|
|
214
|
----------------------------------------------------------
|
|
215
|
Seq Scan on links (cost=0.00..248.01 rows=14 width=224)
|
|
216
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
217
|
(2 rows)
|
|
218
|
|
|
219
|
With index:
|
|
220
|
|
|
221
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
222
|
QUERY PLAN
|
|
223
|
---------------------------------------------------------
|
|
224
|
Seq Scan on links (cost=0.00..248.01 rows=3 width=224)
|
|
225
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
226
|
(2 rows)
|
|
227
|
|
|
228
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
229
|
QUERY PLAN
|
|
230
|
----------------------------------------------------------------------------------------------------------------------
|
|
231
|
Bitmap Heap Scan on links (cost=4.39..43.87 rows=14 width=224)
|
|
232
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
233
|
-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.38 rows=13 width=0)
|
|
234
|
Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
|
|
235
|
(4 rows)
|
|
236
|
|
|
237
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|
|
238
|
========
|
|
239
|
|
|
240
|
With 20,000 rows:
|
|
241
|
|
|
242
|
Without index:
|
|
243
|
|
|
244
|
|
|
245
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
246
|
QUERY PLAN
|
|
247
|
---------------------------------------------------------
|
|
248
|
Seq Scan on links (cost=0.00..484.68 rows=3 width=224)
|
|
249
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
250
|
(2 rows)
|
|
251
|
|
|
252
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
253
|
QUERY PLAN
|
|
254
|
----------------------------------------------------------
|
|
255
|
Seq Scan on links (cost=0.00..484.68 rows=14 width=224)
|
|
256
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
257
|
(2 rows)
|
|
258
|
|
|
259
|
|
|
260
|
With index:
|
|
261
|
|
|
262
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
263
|
QUERY PLAN
|
|
264
|
---------------------------------------------------------
|
|
265
|
Seq Scan on links (cost=0.00..484.68 rows=3 width=224)
|
|
266
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
267
|
(2 rows)
|
|
268
|
|
|
269
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
270
|
QUERY PLAN
|
|
271
|
----------------------------------------------------------------------------------------------------------------------
|
|
272
|
Bitmap Heap Scan on links (cost=4.39..47.42 rows=14 width=224)
|
|
273
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
274
|
-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.39 rows=13 width=0)
|
|
275
|
Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
|
|
276
|
(4 rows)
|
|
277
|
|
|
278
|
|
|
279
|
|
|
280
|
==========
|
|
281
|
|
|
282
|
With 30,000 rows
|
|
283
|
|
|
284
|
Without index:
|
|
285
|
|
|
286
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
287
|
QUERY PLAN
|
|
288
|
---------------------------------------------------------
|
|
289
|
Seq Scan on links (cost=0.00..717.81 rows=4 width=224)
|
|
290
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
291
|
(2 rows)
|
|
292
|
|
|
293
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
294
|
QUERY PLAN
|
|
295
|
----------------------------------------------------------
|
|
296
|
Seq Scan on links (cost=0.00..717.81 rows=20 width=224)
|
|
297
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
298
|
(2 rows)
|
|
299
|
|
|
300
|
|
|
301
|
With index:
|
|
302
|
|
|
303
|
|
|
304
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
305
|
QUERY PLAN
|
|
306
|
---------------------------------------------------------
|
|
307
|
Seq Scan on links (cost=0.00..726.01 rows=3 width=224)
|
|
308
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
309
|
(2 rows)
|
|
310
|
|
|
311
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
312
|
QUERY PLAN
|
|
313
|
----------------------------------------------------------------------------------------------------------------------
|
|
314
|
Bitmap Heap Scan on links (cost=4.39..49.05 rows=14 width=224)
|
|
315
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
316
|
-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.39 rows=13 width=0)
|
|
317
|
Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
|
|
318
|
(4 rows)
|
|
319
|
|
|
320
|
|
|
321
|
|
|
322
|
===========
|
|
323
|
|
|
324
|
With 50,000 rows
|
|
325
|
|
|
326
|
Without index:
|
|
327
|
|
|
328
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
329
|
QUERY PLAN
|
|
330
|
----------------------------------------------------------
|
|
331
|
Seq Scan on links (cost=0.00..1203.01 rows=2 width=223)
|
|
332
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
333
|
(2 rows)
|
|
334
|
|
|
335
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
336
|
QUERY PLAN
|
|
337
|
-----------------------------------------------------------
|
|
338
|
Seq Scan on links (cost=0.00..1203.01 rows=14 width=223)
|
|
339
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
340
|
(2 rows)
|
|
341
|
|
|
342
|
With index:
|
|
343
|
|
|
344
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
345
|
QUERY PLAN
|
|
346
|
----------------------------------------------------------
|
|
347
|
Seq Scan on links (cost=0.00..1203.01 rows=2 width=223)
|
|
348
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
349
|
(2 rows)
|
|
350
|
|
|
351
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
352
|
QUERY PLAN
|
|
353
|
----------------------------------------------------------------------------------------------------------------------
|
|
354
|
Bitmap Heap Scan on links (cost=4.41..54.04 rows=14 width=223)
|
|
355
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
356
|
-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.40 rows=14 width=0)
|
|
357
|
Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
|
|
358
|
(4 rows)
|
|
359
|
|
|
360
|
===========
|
|
361
|
|
|
362
|
With 160,000 rows
|
|
363
|
|
|
364
|
Without index:
|
|
365
|
|
|
366
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
367
|
QUERY PLAN
|
|
368
|
----------------------------------------------------------
|
|
369
|
Seq Scan on links (cost=0.00..3811.89 rows=1 width=225)
|
|
370
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
371
|
(2 rows)
|
|
372
|
|
|
373
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
374
|
QUERY PLAN
|
|
375
|
-----------------------------------------------------------
|
|
376
|
Seq Scan on links (cost=0.00..3811.89 rows=30 width=225)
|
|
377
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
378
|
(2 rows)
|
|
379
|
|
|
380
|
With index:
|
|
381
|
|
|
382
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
383
|
QUERY PLAN
|
|
384
|
----------------------------------------------------------
|
|
385
|
Seq Scan on links (cost=0.00..3828.01 rows=1 width=225)
|
|
386
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
387
|
(2 rows)
|
|
388
|
|
|
389
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
390
|
QUERY PLAN
|
|
391
|
----------------------------------------------------------------------------------------------------------------------
|
|
392
|
Bitmap Heap Scan on links (cost=4.60..113.44 rows=30 width=225)
|
|
393
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
394
|
-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.59 rows=30 width=0)
|
|
395
|
Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
|
|
396
|
(4 rows)
|
|
397
|
|
|
398
|
|
|
399
|
===========
|
|
400
|
|
|
401
|
With 250,000 rows
|
|
402
|
|
|
403
|
Without index:
|
|
404
|
|
|
405
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
406
|
QUERY PLAN
|
|
407
|
----------------------------------------------------------
|
|
408
|
Seq Scan on links (cost=0.00..5985.29 rows=1 width=224)
|
|
409
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
410
|
(2 rows)
|
|
411
|
|
|
412
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
413
|
QUERY PLAN
|
|
414
|
-----------------------------------------------------------
|
|
415
|
Seq Scan on links (cost=0.00..5985.29 rows=11 width=224)
|
|
416
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
417
|
|
|
418
|
|
|
419
|
With index:
|
|
420
|
|
|
421
|
arvados_dev=> explain select * from links where head_uuid like '_____-j7d0g-%';
|
|
422
|
QUERY PLAN
|
|
423
|
----------------------------------------------------------
|
|
424
|
Seq Scan on links (cost=0.00..5985.29 rows=1 width=224)
|
|
425
|
Filter: ((head_uuid)::text ~~ '_____-j7d0g-%'::text)
|
|
426
|
(2 rows)
|
|
427
|
|
|
428
|
arvados_dev=> explain select * from links where head_uuid like 'zzzzz-j7d0g-%';
|
|
429
|
QUERY PLAN
|
|
430
|
----------------------------------------------------------------------------------------------------------------------
|
|
431
|
Bitmap Heap Scan on links (cost=4.43..46.52 rows=11 width=224)
|
|
432
|
Filter: ((head_uuid)::text ~~ 'zzzzz-j7d0g-%'::text)
|
|
433
|
-> Bitmap Index Scan on links_varchar_index_on_head_uuid (cost=0.00..4.42 rows=11 width=0)
|
|
434
|
Index Cond: (((head_uuid)::text ~>=~ 'zzzzz-j7d0g-'::text) AND ((head_uuid)::text ~<~ 'zzzzz-j7d0g.'::text))
|
|
435
|
(4 rows)
|
|
436
|
|