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create table ten(a int);
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insert into ten values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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create table t10 (a int, b int);
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insert into t10 select a,a from ten;
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alter table t10 add key(a);
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set optimizer_trace=1;
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explain delete from t10 where t10.a<3;
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select * from information_schema.optimizer_trace\G
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prints
*************************** 1. row ***************************
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QUERY: explain delete from t10 where t10.a<3
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TRACE: {
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"steps": [
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{
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"table": null,
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"range_analysis": {
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"table_scan": {
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"rows": 10,
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"cost": 5.1
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},
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"potential_range_indexes": [
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