sqlite/test/percentile.test

# 2013-05-28
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is percentile.c extension
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Basic test of the percentile() function.
#
do_test percentile-1.0 {
  load_static_extension db percentile
  execsql {
    CREATE TABLE t1(x);
    INSERT INTO t1 VALUES(1),(4),(6),(7),(8),(9),(11),(11),(11);
  }
  execsql {SELECT percentile(x,0) FROM t1}
} {1.0}
foreach {in out} {
  100    11.0
   50     8.0
   12.5   4.0
   15     4.4
   20     5.2
   80    11.0
   89    11.0
} {
  do_test percentile-1.1.$in {
    execsql {SELECT percentile(x,$in) FROM t1}
  } $out
}

# Add some NULL values.
#
do_test percentile-1.2 {
  execsql {INSERT INTO t1 VALUES(NULL),(NULL);}
} {}
foreach {in out} {
  100    11.0
   50     8.0
   12.5   4.0
   15     4.4
   20     5.2
   80    11.0
   89    11.0
} {
  do_test percentile-1.3.$in {
    execsql {SELECT percentile(x,$in) FROM t1}
  } $out
}

# The second argument to percentile can change some, but not much.
#
do_test percentile-1.4 {
  catchsql {SELECT round(percentile(x, 15+0.000001*rowid),1) FROM t1}
} {0 4.4}
do_test percentile-1.5 {
  catchsql {SELECT round(percentile(x, 15+0.1*rowid),1) FROM t1}
} {1 {2nd argument to percentile() is not the same for all input rows}}

# Input values in a random order
#
do_test percentile-1.6 {
  execsql {
    CREATE TABLE t2(x);
    INSERT INTO t2 SELECT x+0.0 FROM t1 ORDER BY random();
  }
} {}
foreach {in out} {
  100    11.0
   50     8.0
   12.5   4.0
   15     4.4
   20     5.2
   80    11.0
   89    11.0
} {
  do_test percentile-1.7.$in {
    execsql {SELECT percentile(x,$in) FROM t2}
  } $out
}

# Wrong number of arguments
#
do_test percentile-1.8 {
  catchsql {SELECT percentile(x,0,1) FROM t1}
} {1 {wrong number of arguments to function percentile()}}
do_test percentile-1.9 {
  catchsql {SELECT percentile(x) FROM t1}
} {1 {wrong number of arguments to function percentile()}}

# Second argument must be numeric
#
do_test percentile-1.10 {
  catchsql {SELECT percentile(x,null) FROM t1}
} {1 {2nd argument to percentile() is not a number between 0.0 and 100.0}}
do_test percentile-1.11 {
  catchsql {SELECT percentile(x,'fifty') FROM t1}
} {1 {2nd argument to percentile() is not a number between 0.0 and 100.0}}
do_test percentile-1.12 {
  catchsql {SELECT percentile(x,x'3530') FROM t1}
} {1 {2nd argument to percentile() is not a number between 0.0 and 100.0}}

# Second argument is out of range
#
do_test percentile-1.13 {
  catchsql {SELECT percentile(x,-0.0000001) FROM t1}
} {1 {2nd argument to percentile() is not a number between 0.0 and 100.0}}
do_test percentile-1.14 {
  catchsql {SELECT percentile(x,100.0000001) FROM t1}
} {1 {2nd argument to percentile() is not a number between 0.0 and 100.0}}

# First argument is not NULL and is not NUMERIC
#
do_test percentile-1.15 {
  catchsql {
    BEGIN;
    UPDATE t1 SET x='50' WHERE x IS NULL;
    SELECT percentile(x, 50) FROM t1;
  }
} {1 {1st argument to percentile() is not numeric}}
do_test percentile-1.16 {
  catchsql {
    ROLLBACK;
    BEGIN;
    UPDATE t1 SET x=x'3530' WHERE x IS NULL;
    SELECT percentile(x, 50) FROM t1;
  }
} {1 {1st argument to percentile() is not numeric}}
do_test percentile-1.17 {
  catchsql {
    ROLLBACK;
    SELECT percentile(x, 50) FROM t1;
  }
} {0 8.0}

# No non-NULL entries.
#
do_test percentile-1.18 {
  execsql {
    UPDATE t1 SET x=NULL;
    SELECT ifnull(percentile(x, 50),'NULL') FROM t1
  } 
} {NULL}

# Exactly one non-NULL entry
#
do_test percentile-1.19 {
  execsql {
    UPDATE t1 SET x=12345 WHERE rowid=5;
    SELECT percentile(x, 0), percentile(x, 50), percentile(x,100) FROM t1
  } 
} {12345.0 12345.0 12345.0}

# Infinity as an input
#
do_test percentile-1.20 {
  catchsql {
    DELETE FROM t1;
    INSERT INTO t1 SELECT x+0.0 FROM t2;
    UPDATE t1 SET x=1.0e300*1.0e300 WHERE rowid=5;
    SELECT percentile(x,50) from t1;
  }
} {1 {Inf input to percentile()}}
do_test percentile-1.21 {
  catchsql {
    UPDATE t1 SET x=-1.0e300*1.0e300 WHERE rowid=5;
    SELECT percentile(x,50) from t1;
  }
} {1 {Inf input to percentile()}}

# Million-row Inputs
#
ifcapable vtab {
  do_test percentile-2.0 {
    load_static_extension db wholenumber
    execsql {
      CREATE VIRTUAL TABLE nums USING wholenumber;
      CREATE TABLE t3(x);
      INSERT INTO t3 SELECT value-1 FROM nums WHERE value BETWEEN 1 AND 500000;
      INSERT INTO t3 SELECT value*10 FROM nums
                      WHERE value BETWEEN 500000 AND 999999;
      SELECT count(*) FROM t3;
    }
  } {1000000}
  foreach {in out} {
      0          0.0
    100    9999990.0
     50    2749999.5
     10      99999.9
  } {
    do_test percentile-2.1.$in {
      execsql {
        SELECT round(percentile(x, $in),1) from t3;
      }
    } $out
  }
}

finish_test