test/count.test

# 2009 February 24
#
# 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 testing "SELECT count(*)" statements.
#
# $Id: count.test,v 1.4 2009/04/02 20:27:28 drh Exp $

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

# Test plan:
#
#  count-0.*: Make sure count(*) works on an empty database.  (Ticket #3774)
#
#  count-1.*: Test that the OP_Count instruction appears to work on both
#             tables and indexes. Test both when they contain 0 entries,
#             when all entries are on the root page, and when the b-tree
#             forms a structure 2 and 3 levels deep.
#            
#  count-2.*: Test that 
#
#

do_test count-0.1 {
  db eval {
     SELECT count(*) FROM sqlite_master;
  }
} {0}

set iTest 0
foreach zIndex [list {
  /* no-op */
} {
  CREATE INDEX i1 ON t1(a);
}] { 
  incr iTest
  do_test count-1.$iTest.1 {
    execsql {
      DROP TABLE IF EXISTS t1;
      CREATE TABLE t1(a, b);
    }
    execsql $zIndex
    execsql { SELECT count(*) FROM t1 }
  } {0}
  
  do_test count-1.$iTest.2 {
    execsql {
      INSERT INTO t1 VALUES(1, 2);
      INSERT INTO t1 VALUES(3, 4);
      SELECT count(*) FROM t1;
    }
  } {2}

  do_test count-1.$iTest.3 {
    execsql {
      INSERT INTO t1 SELECT * FROM t1;          --   4
      INSERT INTO t1 SELECT * FROM t1;          --   8
      INSERT INTO t1 SELECT * FROM t1;          --  16
      INSERT INTO t1 SELECT * FROM t1;          --  32
      INSERT INTO t1 SELECT * FROM t1;          --  64
      INSERT INTO t1 SELECT * FROM t1;          -- 128
      INSERT INTO t1 SELECT * FROM t1;          -- 256
      SELECT count(*) FROM t1;
    }
  } {256}
  
  do_test count-1.$iTest.4 {
    execsql {
      INSERT INTO t1 SELECT * FROM t1;          --  512
      INSERT INTO t1 SELECT * FROM t1;          -- 1024
      INSERT INTO t1 SELECT * FROM t1;          -- 2048
      INSERT INTO t1 SELECT * FROM t1;          -- 4096
      SELECT count(*) FROM t1;
    }
  } {4096}
  
  do_test count-1.$iTest.5 {
    execsql {
      BEGIN;
      INSERT INTO t1 SELECT * FROM t1;          --  8192
      INSERT INTO t1 SELECT * FROM t1;          -- 16384
      INSERT INTO t1 SELECT * FROM t1;          -- 32768
      INSERT INTO t1 SELECT * FROM t1;          -- 65536
      COMMIT;
      SELECT count(*) FROM t1;
    }
  } {65536}
}

proc uses_op_count {sql} {
  if {[lsearch [execsql "EXPLAIN $sql"] Count]>=0} {
    return 1;
  }
  return 0
}

do_test count-2.1 {
  execsql {
    CREATE TABLE t2(a, b);
  }
  uses_op_count {SELECT count(*) FROM t2}
} {1}
do_test count-2.2 {
  catchsql {SELECT count(DISTINCT *) FROM t2}
} {1 {near "*": syntax error}}
do_test count-2.3 {
  uses_op_count {SELECT count(DISTINCT a) FROM t2}
} {0}
do_test count-2.4 {
  uses_op_count {SELECT count(a) FROM t2}
} {0}
do_test count-2.5 {
  uses_op_count {SELECT count() FROM t2}
} {1}
do_test count-2.6 {
  catchsql {SELECT count(DISTINCT) FROM t2}
} {1 {DISTINCT aggregates must have exactly one argument}}
do_test count-2.7 {
  uses_op_count {SELECT count(*)+1 FROM t2}
} {0}
do_test count-2.8 {
  uses_op_count {SELECT count(*) FROM t2 WHERE a IS NOT NULL}
} {0}
do_test count-2.9 {
  catchsql {SELECT count(*) FROM t2 HAVING count(*)>1}
} {1 {a GROUP BY clause is required before HAVING}}
do_test count-2.10 {
  uses_op_count {SELECT count(*) FROM (SELECT 1)}
} {0}
do_test count-2.11 {
  execsql { CREATE VIEW v1 AS SELECT 1 AS a }
  uses_op_count {SELECT count(*) FROM v1}
} {0}
do_test count-2.12 {
  uses_op_count {SELECT count(*), max(a) FROM t2}
} {0}
do_test count-2.13 {
  uses_op_count {SELECT count(*) FROM t1, t2}
} {0}

ifcapable vtab {
  register_echo_module [sqlite3_connection_pointer db]
  do_test count-2.14 {
    execsql { CREATE VIRTUAL TABLE techo USING echo(t1); }
    uses_op_count {SELECT count(*) FROM techo}
  } {0}
}

do_test count-3.1 {
  execsql {
    CREATE TABLE t3(a, b);
    SELECT a FROM (SELECT count(*) AS a FROM t3) WHERE a==0;
  }
} {0}
do_test count-3.2 {
  execsql {
    SELECT a FROM (SELECT count(*) AS a FROM t3) WHERE a==1;
  }
} {}

do_test count-4.1 {
  execsql {
    CREATE TABLE t4(a, b);
    INSERT INTO t4 VALUES('a', 'b');
    CREATE INDEX t4i1 ON t4(b, a);
    SELECT count(*) FROM t4;
  }
} {1}
do_test count-4.2 {
  execsql {
    CREATE INDEX t4i2 ON t4(b);
    SELECT count(*) FROM t4;
  }
} {1}
do_test count-4.3 {
  execsql {
    DROP INDEX t4i1;
    CREATE INDEX t4i1 ON t4(b, a);
    SELECT count(*) FROM t4;
  }
} {1}


finish_test