postgresql中文首字母查找

-- 测试函数 select fn_get_hz_first('瓧'); -- 删除函数 -- drop function if exists fn_get_hz_first(varchar); create or replace function fn_get_hz_first(ahzstr varchar) returns varchar language plpgsql immutable as $$ declare sresult varchar ; begin with hzlb as( --传入参数列转行 select regexp_split_to_table(ahzstr,'') as hzstr), asclb as( select hzstr,ascii(hzstr) as asicchz from hzlb), hzpdlb as ( --根据字节数判定首字母 select case when asicchz in (20208,20236,20289,20370,20474,20579,20658,20734,20753,20753,20946,20985,21356,21378,21384,21419,21446,21526,21621,21621,21689,21696,21710,21769,21769,21813,21824,21834,21834,21834,21834,21834,21885,21885,21956,21964,21996,21996,22003,22003,22003,22007,22008,22026,22123,22127,22127,22127,22179,22210,22387,22407,22453,22467,22511,22547,22568,22631,22714,22717,22738,22829,22881,22881,22885,22887,23085,23102,23102,23145,23189,23210,23228,23250,23279,23329,23433,23669,23677,23687,23705,23728,23736,23766,23910,23941,23941,23988,24191,24245,24274,24859,24928,24928,25034,25043,25053,25207,25245,25245,25303,25303,25353,25384,25384,25457,25566,25710,25817,25942,25969,25971,26114,26169,26171,26235,26235,26263,26279,26326,26506,26602,26602,26696,26697,26766,27436,27448,27600,27688,27857,27933,28336,28350,28406,28570,28595,28653,28965,29085,29100,29100,29194,29233,29364,29522,29523,29621,29815,29832,29862,30199,30284,30353,30362,30375,30414,30438,30443,30481,30481,30649,30702,30777,30795,30809,30861,30929,30941,31001,32096,32623,32753,32758,32762,32881,32942,33018,33100,33124,33401,33406,33466,33612,33780,33851,33866,34029,34076,34108,34182,34297,34735,34948,35066,35158,35474,35485,35568,35571,35639,35640,35690,35706,35830,35865,35963,35979,36089,36535,36586,36586,36968,37097,37251,37280,37544,37644,37650,37764,37834,37845,37846,37952,38133,38165,38207,38266,38343,38440,38463,38463,38463,38463,38540,38545,38552,38558,38569,38648,38701,38724,38729,38796,38797,38909,39218,39331,39332,39427,39489,39489,39580,39580,39599,39839,39986,40043,40140,40241,40298,40341,40404,40524,40687,40711) then 'a' when asicchz in (23845,23849,19981,19993,20006,20023,20147,20168,20172,20194,20221,20271,20271,20271,20276,20283,20296,20298,20307,20310,20315,20315,20328,20336,20341,20412,20415,20445,20469,20475,20478,20482,20493,20532,20555,20555,20573,20586,20601,20621,20633,20641,20647,20675,20676,20704,20720,20752,20772,20774,20833,20843,20853,20858,20907,20912,21029,21029,21032,21035,21035,21085,21085,21093,21093,21150,21187,21187,21199,21241,21245,21253,21269,21271,21271,21310,21322,21329,21338,21340,21340,21342,21343,21456,21464,21485,21485,21537,21541,21543,21543,21591,21591,21639,21656,21716,21745,21745,21749,21754,21764,21764,21850,21877,21877,21935,21977,22006,22051,22083,22167,22167,22338,22347,22348,22354,22365,22370,22442,22457,22459,22468,22484,22487,22496,22514,22539,22555,22561,22561,22562,22577,22621,22644,22658,22721,22726,22761,22791,22793,22831,22834,22838,22847,22868,22868,22873,22879,22896,22947,22957,22972,22981,23069,23108,23114,23138,23212,23249,23318,23387,23387,23394,23417,23453,23474,23486,23502,23502,23514,23539,23542,23620,23631,23631,23643,23685,23708,23749,23751,23788,23917,23955,24045,24052,24065,24067,24091,24110,24135,24150,24154,24163,24164,24171,24182,24182,24183,24183,24199,24205,24239,24240,24243,24243,24269,24294,24321,24330,24349,24379,24380,24387,24390,24426,24428,24429,24436,24444,24487,24502,24513,24517,24557,24585,24585,24593,24598,24621,24626,24630,24721,24726,24754,24811,24828,24834,24842,24846,24893,24970,24971,25066,25153,25170,25170,25198,25203,25207,25219,25226,25226,25244,25253,25254,25258,25265,25282,25292,25300,25308,25309,25320,25344,25388,25399,25420,25429,25431,25440,25452,25453,25465,25508,25520,25561,25561,25593,25593,25596,25615,25618,25643,25644,25670,25672,25682,25725,25725,25765,25770,25773,25815,25816,25816,25839,25839,25850,25917,25943,25949,25987,25996,26001,26002,26049,26055,26113,26116,26142,26154,26170,26209,26292,26323,26333,26375,26380,26412,26419,26428,26451,26478,26479,26487,26495,26507,26553,26560,26564,26568,26575,26575,26575,26600,26605,26605,26605,26610,26610,26616,26631,26655,26655,26658,26658,26658,26660,26734,26738,26739,26758,26768,26774,26809,26809,26821,26833,26834,26835,26835,26835,26897,26901,26949,26957,27020,27025,27036,27036,27103,27103,27161,27287,27288,27302,27302,27315,27315,27394,27419,27493,27496,27497,27541,27553,27567,27604,27605,27606,27609,27614,27636,27703,27715,27763,27764,27800,27850,27852,27853,27853,27874,27893,27996,28001,28146,28159,28160,28196,28258,28276,28298,28375,28392,28397,28398,28464,28535,28626,28638,28657,28661,28684,28689,28693,28766,28780,28803,28830,28838,28846,28851,28953,29007,29042,29048,29055,29082,29083,29186,29190,29240,29256,29265,29267,29268,29292,29319,29333,29348,29350,29358,29363,29384,29403,29428,29437,29448,29451,29493,29500,29528,29529,29553,29584,29602,29603,29604,29627,29644,29668,29677,29692,29717,29731,29739,29746,29816,29863,29880,29917,29919,29923,29930,29951,29954,29967,29997,29998,30016,30017,30032,30032,30042,30050,30101,30116,30122,30138,30149,30189,30201,30202,30242,30250,30250,30253,30285,30303,30303,30326,30329,30333,30334,30336,30341,30357,30378,30403,30411,30506,30564,30565,30706,30735,30765,30773,30821,30854,30865,30874,30885,30887,30917,30950,30971,31009,31028,31050,31061,31104,31110,31129,31177,31189,31192,31194,31201,31254,31255,31263,31272,31275,31323,31342,31366,31367,31369,31453,31457,31494,31507,31508,31523,31528,31550,31558,31578,31617,31620,31620,31621,31622,31636,31663,31718,31728,31731,31739,31769,31800,31800,31807,31807,31827,31849,31875,31876,31882,31889,31912,31930,31940,31940,31954,31978,32021,32052,32052,32070,32084,32099,32099,32129,32134,32179,32179,32179,32188,32229,32232,32246,32269,32269,32298,32323,32323,32323,32372,32381,32432,32458,32465,32480,32503,32503,32503,32527,32534,32548,32573,32610,32610,32631,32631,32636,32659,32713,32717,32793,32859,32913,32934,32950,32950,32967,32968,32969,32972,32972,32990,33046,33087,33143,33152,33152,33162,33162,33169,33172,33176,33218,33218,33231,33237,33265,33320,33324,33324,33325,33334,33354,33361,33365,33432,33453,33476,33501,33502,33513,33514,33519,33534,33543,33628,33656,33657,33666,33757,33760,33762,33782,33798,33822,33825,33849,33849,33862,33895,33953,34003,34006,34045,34048,34056,34068,34068,34109,34115,34132,34180,34180,34180,34204,34221,34250,34275,34280,34293,34327,34380,34403,34408,34436,34438,34444,34444,34475,34494,34498,34499,34499,34518,34557,34572,34607,34607,34626,34649,34689,34700,34709,34782,34782,34790,34841,34917,34920,34956,34960,34987,34991,35001,35036,35046,35048,35057,35082,35090,35090,35091,35097,35113,35134,35139,35151,35154,35166,35171,35180,35182,35207,35213,35253,35313,35414,35417,35457,35478,35478,35495,35520,35544,35546,35592,35607,35620,35666,35722,35792,35876,35917,35933,35945,35955,35961,35983,35997,36017,36022,36033,36033,36051,36052,36082,36097,36102,36116,36125,36133,36140,36146,36146,36177,36277,36277,36289,36299,36312,36315,36336,36344,36356,36387,36437,36454,36457,36467,36483,36484,36592,36599,36649,36688,36744,36767,36769,36774,36775,36776,36777,36779,36780,36782,36783,36793,36794,36810,36856,36875,36905,36908,36924,36941,36991,37001,37002,37024,37030,37035,37042,37044,37046,37091,37093,37096,37110,37121,37145,37160,37162,37293,37318,37343,37376,37384,37393,37429,37432,37437,37451,37453,37457,37473,37474,37491,37500,37575,37581,37618,37659,37686,37691,37757,37770,37787,37790,37790,37838,37858,37872,37940,37950,37964,37987,37988,37998,38042,38049,38051,38063,38069,38072,38073,38082,38087,38091,38171,38216,38225,38228,38230,38234,38259,38279,38280,38281,38285,38302,38303,38337,38342,38380,38381,38442,38466,38467,38476,38491,38649,38694,38712,38732,38736,38774,38774,38781,38785,38790,38805,38811,38814,38814,38814,38820,38829,38836,38840,38840,38875,38880,38930,38971,39022,39041,39057,39081,3