AryaWu/sqlite

1# 2001 September 152#3# The author disclaims copyright to this source code.  In place of4# a legal notice, here is a blessing:5#6#    May you do good and not evil.7#    May you find forgiveness for yourself and forgive others.8#    May you share freely, never taking more than you give.9#10#***********************************************************************11# This file implements regression tests for SQLite library.12#13# This file implements tests for proper treatment of the special14# value NULL.15#16 17set testdir [file dirname $argv0]18source $testdir/tester.tcl19 20# Create a table and some data to work with.21#22do_test null-1.0 {23  execsql {24    begin;25    create table t1(a,b,c);26    insert into t1 values(1,0,0);27    insert into t1 values(2,0,1);28    insert into t1 values(3,1,0);29    insert into t1 values(4,1,1);30    insert into t1 values(5,null,0);31    insert into t1 values(6,null,1);32    insert into t1 values(7,null,null);33    commit;34    select * from t1;35  }36} {1 0 0 2 0 1 3 1 0 4 1 1 5 {} 0 6 {} 1 7 {} {}}37 38# Check for how arithmetic expressions handle NULL39#40do_test null-1.1 {41  execsql {42    select ifnull(a+b,99) from t1;43  }44} {1 2 4 5 99 99 99}45do_test null-1.2 {46  execsql {47    select ifnull(b*c,99) from t1;48  }49} {0 0 0 1 99 99 99}50 51# Check to see how the CASE expression handles NULL values.  The52# first WHEN for which the test expression is TRUE is selected.53# FALSE and UNKNOWN test expressions are skipped.54#55do_test null-2.1 {56  execsql {57    select ifnull(case when b<>0 then 1 else 0 end, 99) from t1;58  }59} {0 0 1 1 0 0 0}60do_test null-2.2 {61  execsql {62    select ifnull(case when not b<>0 then 1 else 0 end, 99) from t1;63  }64} {1 1 0 0 0 0 0}65do_test null-2.3 {66  execsql {67    select ifnull(case when b<>0 and c<>0 then 1 else 0 end, 99) from t1;68  }69} {0 0 0 1 0 0 0}70do_test null-2.4 {71  execsql {72    select ifnull(case when not (b<>0 and c<>0) then 1 else 0 end, 99) from t1;73  }74} {1 1 1 0 1 0 0}75do_test null-2.5 {76  execsql {77    select ifnull(case when b<>0 or c<>0 then 1 else 0 end, 99) from t1;78  }79} {0 1 1 1 0 1 0}80do_test null-2.6 {81  execsql {82    select ifnull(case when not (b<>0 or c<>0) then 1 else 0 end, 99) from t1;83  }84} {1 0 0 0 0 0 0}85do_test null-2.7 {86  execsql {87    select ifnull(case b when c then 1 else 0 end, 99) from t1;88  }89} {1 0 0 1 0 0 0}90do_test null-2.8 {91  execsql {92    select ifnull(case c when b then 1 else 0 end, 99) from t1;93  }94} {1 0 0 1 0 0 0}95 96# Check to see that NULL values are ignored in aggregate functions.97#98do_test null-3.1 {99  execsql {100    select count(*), count(b), count(c), sum(b), sum(c), 101           avg(b), avg(c), min(b), max(b) from t1;102  }103} {7 4 6 2 3 0.5 0.5 0 1}104 105# The sum of zero entries is a NULL, but the total of zero entries is 0.106#107do_test null-3.2 {108  execsql {109    SELECT sum(b), total(b) FROM t1 WHERE b<0110  }111} {{} 0.0}112 113# Check to see how WHERE clauses handle NULL values.  A NULL value114# is the same as UNKNOWN.  The WHERE clause should only select those115# rows that are TRUE.  FALSE and UNKNOWN rows are rejected.116#117do_test null-4.1 {118  execsql {119    select a from t1 where b<10120  }121} {1 2 3 4}122do_test null-4.2 {123  execsql {124    select a from t1 where not b>10125  }126} {1 2 3 4}127do_test null-4.3 {128  execsql {129    select a from t1 where b<10 or c=1;130  }131} {1 2 3 4 6}132do_test null-4.4 {133  execsql {134    select a from t1 where b<10 and c=1;135  }136} {2 4}137do_test null-4.5 {138  execsql {139    select a from t1 where not (b<10 and c=1);140  }141} {1 3 5}142 143# The DISTINCT keyword on a SELECT statement should treat NULL values144# as distinct145#146do_test null-5.1 {147  execsql {148    select distinct b from t1 order by b;149  }150} {{} 0 1}151 152# A UNION to two queries should treat NULL values153# as distinct.154#155# (Later:)  We also take this opportunity to test the ability156# of an ORDER BY clause to bind to either SELECT of a UNION.157# The left-most SELECT is preferred.  In standard SQL, only158# the left SELECT can be used.  The ability to match an ORDER159# BY term to the right SELECT is an SQLite extension.160#161ifcapable compound {162  do_test null-6.1 {163    execsql {164      select b from t1 union select c from t1 order by b;165    }166  } {{} 0 1}167  do_test null-6.2 {168    execsql {169      select b from t1 union select c from t1 order by 1;170    }171  } {{} 0 1}172  do_test null-6.3 {173    execsql {174      select b from t1 union select c from t1 order by t1.b;175    }176  } {{} 0 1}177  do_test null-6.4 {178    execsql {179      select b from t1 union select c from t1 order by main.t1.b;180    }181  } {{} 0 1}182  do_test null-6.5 {183    catchsql {184      select b from t1 union select c from t1 order by t1.a;185    }186  } {1 {1st ORDER BY term does not match any column in the result set}}187  do_test null-6.6 {188    catchsql {189      select b from t1 union select c from t1 order by main.t1.a;190    }191  } {1 {1st ORDER BY term does not match any column in the result set}}192} ;# ifcapable compound193 194# The UNIQUE constraint only applies to non-null values195#196ifcapable conflict {197do_test null-7.1 {198    execsql {199      create table t2(a, b unique on conflict ignore);200      insert into t2 values(1,1);201      insert into t2 values(2,null);202      insert into t2 values(3,null);203      insert into t2 values(4,1);204      select a from t2;205    }206  } {1 2 3}207  do_test null-7.2 {208    execsql {209      create table t3(a, b, c, unique(b,c) on conflict ignore);210      insert into t3 values(1,1,1);211      insert into t3 values(2,null,1);212      insert into t3 values(3,null,1);213      insert into t3 values(4,1,1);214      select a from t3;215    }216  } {1 2 3}217}218 219# Ticket #461 - Make sure nulls are handled correctly when doing a220# lookup using an index.221#222do_test null-8.1 {223  execsql {224    CREATE TABLE t4(x,y);225    INSERT INTO t4 VALUES(1,11);226    INSERT INTO t4 VALUES(2,NULL);227    SELECT x FROM t4 WHERE y=NULL;228  }229} {}230ifcapable subquery {231  do_test null-8.2 {232    execsql {233      SELECT x FROM t4 WHERE y IN (33,NULL);234    }235  } {}236}237do_test null-8.3 {238  execsql {239    SELECT x FROM t4 WHERE y<33 ORDER BY x;240  }241} {1}242do_test null-8.4 {243  execsql {244    SELECT x FROM t4 WHERE y>6 ORDER BY x;245  }246} {1}247do_test null-8.5 {248  execsql {249    SELECT x FROM t4 WHERE y!=33 ORDER BY x;250  }251} {1}252do_test null-8.11 {253  execsql {254    CREATE INDEX t4i1 ON t4(y);255    SELECT x FROM t4 WHERE y=NULL;256  }257} {}258ifcapable subquery {259  do_test null-8.12 {260    execsql {261      SELECT x FROM t4 WHERE y IN (33,NULL);262    }263  } {}264}265do_test null-8.13 {266  execsql {267    SELECT x FROM t4 WHERE y<33 ORDER BY x;268  }269} {1}270do_test null-8.14 {271  execsql {272    SELECT x FROM t4 WHERE y>6 ORDER BY x;273  }274} {1}275do_test null-8.15 {276  execsql {277    SELECT x FROM t4 WHERE y!=33 ORDER BY x;278  }279} {1}280 281do_execsql_test null-9.1 {282  CREATE TABLE t5(a, b, c);283  CREATE UNIQUE INDEX t5ab ON t5(a, b);284 285  INSERT INTO t5 VALUES(1, NULL, 'one');286  INSERT INTO t5 VALUES(1, NULL, 'i');287  INSERT INTO t5 VALUES(NULL, 'x', 'two');288  INSERT INTO t5 VALUES(NULL, 'x', 'ii');289}290 291do_execsql_test null-9.2 {292  SELECT * FROM t5 WHERE a = 1 AND b IS NULL;293} {1 {} one 1 {} i}294 295do_execsql_test null-9.3 {296  SELECT * FROM t5 WHERE a IS NULL AND b = 'x';297} {{} x two {} x ii}298 299# 2020-09-30 ticket 5c4e7aa793943803300reset_db301do_execsql_test null-10.1 {302  CREATE TABLE t0(c0 PRIMARY KEY DESC);303  INSERT INTO t0(c0) VALUES (0);304  SELECT * FROM t0 WHERE t0.c0 > NULL;305} {}306 307finish_test308