taos> select SUBSTRING('Hello.World!', 1) substring('Hello.World!', 1) | =============================== Hello.World! | taos> select SUBSTRING('Hello.World!', 1, 5) substring('Hello.World!', 1, 5) | ================================== Hello | taos> select SUBSTRING('Hello.World!', 1, 20) substring('Hello.World!', 1, 20) | =================================== Hello.World! | taos> select SUBSTRING('Hello.World!' FROM 1) substring('Hello.World!' from 1) | =================================== Hello.World! | taos> select SUBSTRING('Hello.World!' FROM 1 FOR 5) substring('Hello.World!' from 1 for 5) | ========================================= Hello | taos> select SUBSTRING('Hello.World!' FROM 1 FOR 20) substring('Hello.World!' from 1 for 20) | ========================================== Hello.World! | taos> select SUBSTRING('Hello.World!', -6) substring('Hello.World!', -6) | ================================ World! | taos> select SUBSTRING('Hello.World!', -6, 5) substring('Hello.World!', -6, 5) | =================================== World | taos> select SUBSTRING('Hello.World!', -6, 20) substring('Hello.World!', -6, 20) | ==================================== World! | taos> select SUBSTRING('Hello.World!' FROM -6) substring('Hello.World!' from -6) | ==================================== World! | taos> select SUBSTRING('Hello.World!' FROM -6 FOR 5) substring('Hello.World!' from -6 for 5) | ========================================== World | taos> select SUBSTRING('Hello.World!' FROM -6 FOR 20) substring('Hello.World!' from -6 for 20) | =========================================== World! | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.', 1) substring('北京涛思数据科技有限公司，tdengine.', 1) | =================================================================== 北京涛思数据科技有限公司，tdengine. | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.', 1, 5) substring('北京涛思数据科技有限公司，tdengine.', 1, | =================================================================== 北京涛思数 | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.', 1, 20) substring('北京涛思数据科技有限公司，tdengine.', 1, | =================================================================== 北京涛思数据科技有限公司，tdengin | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.' FROM 1) substring('北京涛思数据科技有限公司，tdengine.' fro | =================================================================== 北京涛思数据科技有限公司，tdengine. | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.' FROM 1 FOR 5) substring('北京涛思数据科技有限公司，tdengine.' fro | =================================================================== 北京涛思数 | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.' FROM 1 FOR 20) substring('北京涛思数据科技有限公司，tdengine.' fro | =================================================================== 北京涛思数据科技有限公司，tdengin | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.', -6) substring('北京涛思数据科技有限公司，tdengine.', -6 | =================================================================== ngine. | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.', -6, 5) substring('北京涛思数据科技有限公司，tdengine.', -6 | =================================================================== ngine | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.', -6, 20) substring('北京涛思数据科技有限公司，tdengine.', -6 | =================================================================== ngine. | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.' FROM -6) substring('北京涛思数据科技有限公司，tdengine.' fro | =================================================================== ngine. | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.' FROM -6 FOR 5) substring('北京涛思数据科技有限公司，tdengine.' fro | =================================================================== ngine | taos> select SUBSTRING('北京涛思数据科技有限公司，tdengine.' FROM -6 FOR 20) substring('北京涛思数据科技有限公司，tdengine.' fro | =================================================================== ngine. | taos> select SUBSTRING(nch1, 1) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, 1) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTRING(nch1, 1, 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, 1, 5) | ================================= 一二三四五 | prisi | 一二三四五 | prisi | abc一二 | taos> select SUBSTRING(nch1, 1, 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, 1, 20) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTRING(nch1 FROM 1) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from 1) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTRING(nch1 FROM 1 FOR 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from 1 for 5) | ================================= 一二三四五 | prisi | 一二三四五 | prisi | abc一二 | taos> select SUBSTRING(nch1 FROM 1 FOR 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from 1 for 20) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTRING(nch1, -6) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, -6) | ================================= 五六七八九十 | rision | 五六七八九十 | rision | 一二三abc | taos> select SUBSTRING(nch1, -6, 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, -6, 5) | ================================= 五六七八九 | risio | 五六七八九 | risio | 一二三ab | taos> select SUBSTRING(nch1, -6, 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, -6, 20) | ================================= 五六七八九十 | rision | 五六七八九十 | rision | 一二三abc | taos> select SUBSTRING(nch1 FROM -6) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from -6) | ================================= 五六七八九十 | rision | 五六七八九十 | rision | 一二三abc | taos> select SUBSTRING(nch1 FROM -6 FOR 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from -6 for 5) | ================================= 五六七八九 | risio | 五六七八九 | risio | 一二三ab | taos> select SUBSTRING(nch1 FROM -6 FOR 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from -6 for 20) | ================================= 五六七八九十 | rision | 五六七八九十 | rision | 一二三abc | taos> select SUBSTRING(var1, 1) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, 1) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTRING(var1, 1, 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, 1, 5) | ================================= 一二三四五 | prisi | prisi | abc一二 | 一二三12 | taos> select SUBSTRING(var1, 1, 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, 1, 20) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTRING(var1 FROM 1) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from 1) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTRING(var1 FROM 1 FOR 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from 1 for 5) | ================================= 一二三四五 | prisi | prisi | abc一二 | 一二三12 | taos> select SUBSTRING(var1 FROM 1 FOR 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from 1 for 20) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTRING(var1, -6) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, -6) | ================================= 五六七八九十 | rision | rision | 一二三abc | 321三二一 | taos> select SUBSTRING(var1, -6, 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, -6, 5) | ================================= 五六七八九 | risio | risio | 一二三ab | 321三二 | taos> select SUBSTRING(var1, -6, 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, -6, 20) | ================================= 五六七八九十 | rision | rision | 一二三abc | 321三二一 | taos> select SUBSTRING(var1 FROM -6) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from -6) | ================================= 五六七八九十 | rision | rision | 一二三abc | 321三二一 | taos> select SUBSTRING(var1 FROM -6 FOR 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from -6 for 5) | ================================= 五六七八九 | risio | risio | 一二三ab | 321三二 | taos> select SUBSTRING(var1 FROM -6 FOR 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from -6 for 20) | ================================= 五六七八九十 | rision | rision | 一二三abc | 321三二一 | taos> select SUBSTRING(nch1, sign(id), 1) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, sign(id), 1) | ================================= 一 | p | 一 | p | a | taos> select SUBSTRING(nch1, sign(id), 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, sign(id), 5) | ================================= 一二三四五 | prisi | 一二三四五 | prisi | abc一二 | taos> select SUBSTRING(nch1, sign(id), 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, sign(id), 20) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTRING(nch1 FROM sign(id)) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from sign(id)) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTRING(nch1 FROM sign(id) FOR 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from sign(id) for 5) | ====================================== 一二三四五 | prisi | 一二三四五 | prisi | abc一二 | taos> select SUBSTRING(nch1 FROM sign(id) FOR 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from sign(id) for 20) | ======================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTRING(var1, sign(id), 1) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, sign(id), 1) | ================================= 一 | p | p | a | 一 | taos> select SUBSTRING(var1, sign(id), 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, sign(id), 5) | ================================= 一二三四五 | prisi | prisi | abc一二 | 一二三12 | taos> select SUBSTRING(var1, sign(id), 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, sign(id), 20) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTRING(var1 FROM sign(id)) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from sign(id)) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTRING(var1 FROM sign(id) FOR 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from sign(id) for 5) | ====================================== 一二三四五 | prisi | prisi | abc一二 | 一二三12 | taos> select SUBSTRING(var1 FROM sign(id) FOR 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from sign(id) for 20) | ======================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTRING(nch1, 2, id) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1, 2, id) | ================================= 二 | ris | 二三四五六七八 | rision | bc一二三abc一二三a | taos> select SUBSTRING(nch1 FROM 2 FOR id) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substring(nch1 from 2 for id) | ================================= 二 | ris | 二三四五六七八 | rision | bc一二三abc一二三a | taos> select SUBSTRING(var1, 2, id) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1, 2, id) | ================================= 二三四五 | rision | rision | bc一二三abc一二三a | 二三123321三二一 | taos> select SUBSTRING(var1 FROM 2 FOR id) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substring(var1 from 2 for id) | ================================= 二三四五 | rision | rision | bc一二三abc一二三a | 二三123321三二一 | taos> select SUBSTR('Hello.World!', 1) substr('Hello.World!', 1) | ============================ Hello.World! | taos> select SUBSTR('Hello.World!', 1, 5) substr('Hello.World!', 1, 5) | =============================== Hello | taos> select SUBSTR('Hello.World!', 1, 20) substr('Hello.World!', 1, 20) | ================================ Hello.World! | taos> select SUBSTR('Hello.World!' FROM 1) substr('Hello.World!' from 1) | ================================ Hello.World! | taos> select SUBSTR('Hello.World!' FROM 1 FOR 5) substr('Hello.World!' from 1 for 5) | ====================================== Hello | taos> select SUBSTR('Hello.World!' FROM 1 FOR 20) substr('Hello.World!' from 1 for 20) | ======================================= Hello.World! | taos> select SUBSTR('Hello.World!', -6) substr('Hello.World!', -6) | ============================= World! | taos> select SUBSTR('Hello.World!', -6, 5) substr('Hello.World!', -6, 5) | ================================ World | taos> select SUBSTR('Hello.World!', -6, 20) substr('Hello.World!', -6, 20) | ================================= World! | taos> select SUBSTR('Hello.World!' FROM -6) substr('Hello.World!' from -6) | ================================= World! | taos> select SUBSTR('Hello.World!' FROM -6 FOR 5) substr('Hello.World!' from -6 for 5) | ======================================= World | taos> select SUBSTR('Hello.World!' FROM -6 FOR 20) substr('Hello.World!' from -6 for 20) | ======================================== World! | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.', 1) substr('北京涛思数据科技有限公司，tdengine.', 1) | ================================================================ 北京涛思数据科技有限公司，tdengine. | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.', 1, 5) substr('北京涛思数据科技有限公司，tdengine.', 1, 5) | =================================================================== 北京涛思数 | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.', 1, 20) substr('北京涛思数据科技有限公司，tdengine.', 1, 20 | =================================================================== 北京涛思数据科技有限公司，tdengin | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.' FROM 1) substr('北京涛思数据科技有限公司，tdengine.' from 1 | =================================================================== 北京涛思数据科技有限公司，tdengine. | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.' FROM 1 FOR 5) substr('北京涛思数据科技有限公司，tdengine.' from 1 | =================================================================== 北京涛思数 | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.' FROM 1 FOR 20) substr('北京涛思数据科技有限公司，tdengine.' from 1 | =================================================================== 北京涛思数据科技有限公司，tdengin | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.', -6) substr('北京涛思数据科技有限公司，tdengine.', -6) | ================================================================= ngine. | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.', -6, 5) substr('北京涛思数据科技有限公司，tdengine.', -6, 5 | =================================================================== ngine | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.', -6, 20) substr('北京涛思数据科技有限公司，tdengine.', -6, 2 | =================================================================== ngine. | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.' FROM -6) substr('北京涛思数据科技有限公司，tdengine.' from - | =================================================================== ngine. | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.' FROM -6 FOR 5) substr('北京涛思数据科技有限公司，tdengine.' from - | =================================================================== ngine | taos> select SUBSTR('北京涛思数据科技有限公司，tdengine.' FROM -6 FOR 20) substr('北京涛思数据科技有限公司，tdengine.' from - | =================================================================== ngine. | taos> select SUBSTR(nch1, 1) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, 1) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTR(nch1, 1, 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, 1, 5) | ================================= 一二三四五 | prisi | 一二三四五 | prisi | abc一二 | taos> select SUBSTR(nch1, 1, 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, 1, 20) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTR(nch1 FROM 1) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from 1) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTR(nch1 FROM 1 FOR 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from 1 for 5) | ================================= 一二三四五 | prisi | 一二三四五 | prisi | abc一二 | taos> select SUBSTR(nch1 FROM 1 FOR 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from 1 for 20) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTR(nch1, -6) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, -6) | ================================= 五六七八九十 | rision | 五六七八九十 | rision | 一二三abc | taos> select SUBSTR(nch1, -6, 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, -6, 5) | ================================= 五六七八九 | risio | 五六七八九 | risio | 一二三ab | taos> select SUBSTR(nch1, -6, 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, -6, 20) | ================================= 五六七八九十 | rision | 五六七八九十 | rision | 一二三abc | taos> select SUBSTR(nch1 FROM -6) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from -6) | ================================= 五六七八九十 | rision | 五六七八九十 | rision | 一二三abc | taos> select SUBSTR(nch1 FROM -6 FOR 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from -6 for 5) | ================================= 五六七八九 | risio | 五六七八九 | risio | 一二三ab | taos> select SUBSTR(nch1 FROM -6 FOR 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from -6 for 20) | ================================= 五六七八九十 | rision | 五六七八九十 | rision | 一二三abc | taos> select SUBSTR(var1, 1) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, 1) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTR(var1, 1, 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, 1, 5) | ================================= 一二三四五 | prisi | prisi | abc一二 | 一二三12 | taos> select SUBSTR(var1, 1, 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, 1, 20) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTR(var1 FROM 1) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from 1) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTR(var1 FROM 1 FOR 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from 1 for 5) | ================================= 一二三四五 | prisi | prisi | abc一二 | 一二三12 | taos> select SUBSTR(var1 FROM 1 FOR 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from 1 for 20) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTR(var1, -6) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, -6) | ================================= 五六七八九十 | rision | rision | 一二三abc | 321三二一 | taos> select SUBSTR(var1, -6, 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, -6, 5) | ================================= 五六七八九 | risio | risio | 一二三ab | 321三二 | taos> select SUBSTR(var1, -6, 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, -6, 20) | ================================= 五六七八九十 | rision | rision | 一二三abc | 321三二一 | taos> select SUBSTR(var1 FROM -6) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from -6) | ================================= 五六七八九十 | rision | rision | 一二三abc | 321三二一 | taos> select SUBSTR(var1 FROM -6 FOR 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from -6 for 5) | ================================= 五六七八九 | risio | risio | 一二三ab | 321三二 | taos> select SUBSTR(var1 FROM -6 FOR 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from -6 for 20) | ================================= 五六七八九十 | rision | rision | 一二三abc | 321三二一 | taos> select SUBSTR(nch1, sign(id), 1) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, sign(id), 1) | ================================= 一 | p | 一 | p | a | taos> select SUBSTR(nch1, sign(id), 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, sign(id), 5) | ================================= 一二三四五 | prisi | 一二三四五 | prisi | abc一二 | taos> select SUBSTR(nch1, sign(id), 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, sign(id), 20) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTR(nch1 FROM sign(id)) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from sign(id)) | ================================= 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTR(nch1 FROM sign(id) FOR 5) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from sign(id) for 5) | =================================== 一二三四五 | prisi | 一二三四五 | prisi | abc一二 | taos> select SUBSTR(nch1 FROM sign(id) FOR 20) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from sign(id) for 20) | ==================================== 一二三四五六七八九十 | prision | 一二三四五六七八九十 | prision | abc一二三abc一二三abc | taos> select SUBSTR(var1, sign(id), 1) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, sign(id), 1) | ================================= 一 | p | p | a | 一 | taos> select SUBSTR(var1, sign(id), 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, sign(id), 5) | ================================= 一二三四五 | prisi | prisi | abc一二 | 一二三12 | taos> select SUBSTR(var1, sign(id), 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, sign(id), 20) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTR(var1 FROM sign(id)) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from sign(id)) | ================================= 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTR(var1 FROM sign(id) FOR 5) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from sign(id) for 5) | =================================== 一二三四五 | prisi | prisi | abc一二 | 一二三12 | taos> select SUBSTR(var1 FROM sign(id) FOR 20) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from sign(id) for 20) | ==================================== 一二三四五六七八九十 | prision | prision | abc一二三abc一二三abc | 一二三123321三二一 | taos> select SUBSTR(nch1, 2, id) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1, 2, id) | ================================= 二 | ris | 二三四五六七八 | rision | bc一二三abc一二三a | taos> select SUBSTR(nch1 FROM 2 FOR id) from ts_4893.meters where char_length(nch1) > 6 order by ts limit 5 substr(nch1 from 2 for id) | ================================= 二 | ris | 二三四五六七八 | rision | bc一二三abc一二三a | taos> select SUBSTR(var1, 2, id) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1, 2, id) | ================================= 二三四五 | rision | rision | bc一二三abc一二三a | 二三123321三二一 | taos> select SUBSTR(var1 FROM 2 FOR id) from ts_4893.meters where char_length(var1) > 6 order by ts limit 5 substr(var1 from 2 for id) | ================================= 二三四五 | rision | rision | bc一二三abc一二三a | 二三123321三二一 | taos> select substring('tdengine', 2) substring('tdengine', 2) | =========================== dengine | taos> select substring('tdengine', 8) substring('tdengine', 8) | =========================== e | taos> select substring('tdengine', 1, 3) substring('tdengine', 1, 3) | ============================== tde | taos> select substring('tdengine', 2, 99) substring('tdengine', 2, 99) | =============================== dengine | taos> select substring('tdengine', -1, 10) substring('tdengine', -1, 10) | ================================ e | taos> select substring('中国', 1, 3) substring('中国', 1, 3) | ============================ 中国 | taos> select substring('中国tdengine', 1, 3) substring('中国tdengine', 1, 3) | ==================================== 中国t | taos> select substring(var1, 1, 5) from ts_4893.d0 order by ts limit 10 substring(var1, 1, 5) | ================================= novel | perso | novel | plate | 一二三四五 | updat | prisi | perso | prisi | plate | taos> select substring(var1, 1, 5) from ts_4893.meters order by ts limit 10 substring(var1, 1, 5) | ================================= novel | perso | novel | plate | 一二三四五 | updat | prisi | perso | prisi | plate | taos> select substring(nch1, 1, 5) from ts_4893.d0 order by ts limit 10 substring(nch1, 1, 5) | ================================= novel | 一二三四五 | updat | prisi | novel | novel | again | 一二三四五 | novel | again | taos> select substring(nch1, 1, 5) from ts_4893.meters order by ts limit 10 substring(nch1, 1, 5) | ================================= novel | 一二三四五 | updat | prisi | novel | novel | again | 一二三四五 | novel | again | taos> select substring(null, 1, 3) substring(null, 1, 3) | ======================== NULL | taos> select substring('tdengine', null, 3) substring('tdengine', null, 3) | ================================= NULL | taos> select substring('tdengine', 0) substring('tdengine', 0) | =========================== | taos> select substring('tdengine', 10) substring('tdengine', 10) | ============================ | taos> select substring('tdengine', 1, null) substring('tdengine', 1, null) | ================================= NULL | taos> select substring('tdengine', 1, 0) substring('tdengine', 1, 0) | ============================== | taos> select substring('tdengine', 1, -1) substring('tdengine', 1, -1) | =============================== | taos> select substr(null, 1, 3) substr(null, 1, 3) | ===================== NULL | taos> select substr('Hello', 1, 3) substr('Hello', 1, 3) | ======================== Hel | taos> select substr('', 1, 5) substr('', 1, 5) | =================== | taos> select substr('ABCDE', 0, 3) substr('ABCDE', 0, 3) | ======================== | taos> select substr('ABCDEFG', -3, 2) substr('ABCDEFG', -3, 2) | =========================== EF | taos> select substr('HelloWorld', 2, 5) substr('HelloWorld', 2, 5) | ============================= elloW | taos> select substr('1234567890', -5, 5) substr('1234567890', -5, 5) | ============================== 67890 | taos> select substr('!@#$%^&*()', 2, 4) substr('!@#$%^&*()', 2, 4) | ============================= @#$% | taos> select substr('你好世界', 3, 2) substr('你好世界', 3, 2) | =============================== 世界 | taos> select substr('ABCDEFG', 10, 5) substr('ABCDEFG', 10, 5) | =========================== | taos> select substr('ABCDEFG', -1, 3) substr('ABCDEFG', -1, 3) | =========================== G | taos> select substr('1234567890', -15, 5) substr('1234567890', -15, 5) | =============================== 12345 | taos> select substr(concat('Hello', 'World'), 1, 5) substr(concat('Hello', 'World'), 1, 5) | ========================================= Hello | taos> select substr('HelloWorld', 1, length('Hello')) substr('HelloWorld', 1, length('Hello')) | =========================================== Hello | taos> select substr(upper('helloworld'), 2, 4) substr(upper('helloworld'), 2, 4) | ==================================== ELLO | taos> select substr(trim(' HelloWorld '), 1, 5) substr(trim(' HelloWorld '), 1, 5) | ======================================= Hello | taos> select name, substr(name, 1, 3) from ts_4893.meters limit 1 name | substr(name, 1, 3) | ================================================================== lili | lil | taos> select var1, substr(var1, 1, 6) from ts_4893.meters limit 1 var1 | substr(var1, 1, 6) | ================================================================== novel | novel | taos> select nch1, substr(nch1, 2, 4) from ts_4893.meters limit 1 nch1 | substr(nch1, 2, 4) | ================================================================== novel | ovel |