SQL Server/T-SQL/Data Type/Bit

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bit type column

 
4> CREATE TABLE T (
5>     int1 int IDENTITY PRIMARY KEY,
6>     bit1 bit NOT NULL DEFAULT 0
7> )
8> GO
1>
2> INSERT T (bit1) VALUES (1)
3> INSERT T (bit1) VALUES (0)
4> INSERT T DEFAULT VALUES
5> INSERT T (int1, bit1) VALUES (4,1)
6> GO
(1 rows affected)
(1 rows affected)
(1 rows affected)
Msg 544, Level 16, State 1, Server J\SQLEXPRESS, Line 5
Cannot insert explicit value for identity column in table "T" when IDENTITY_INSERT is set to OFF.
1>
2> select * from t;
3> GO
int1        bit1
----------- ----
          1    1
          2    0
          3    0
(3 rows affected)
1>
2> drop table t;
3> GO



Count null bit1 values

1>
2> CREATE TABLE T (
3>     int1 int,
4>     bit1 bit,
5>     varchar1 varchar(3),
6>     dec1 dec(5,2),
7>     cmp1 AS (int1 + bit1)
8> )
9> GO
1> INSERT T (int1, bit1) VALUES (1, 0)
2> GO
(1 rows affected)
1> INSERT T (int1, varchar1) VALUES (2, "abc")
2> GO
(1 rows affected)
1> INSERT T (int1, dec1) VALUES (3, 5.25)
2> GO
(1 rows affected)
1> INSERT T (bit1, dec1) VALUES (1, 9.75)
2> GO
(1 rows affected)
1> --Count null bit1 values
2> SELECT COUNT(*) "Count of null bit1"
3> FROM T
4> WHERE bit1 IS NULL
5> GO
Count of null bit1
------------------
                 2
(1 rows affected)
1>
2> drop table t
3> GO
1>
2>