Except in SQLite where as a documented behavioural anomaly maintained for
backwards compatibility it simply means "UNIQUE" (for ROWID tables). And
UNIQUE indexes may have NULL components. This is because despite your wishing
that your primary key is the primary key, it is not the primary key.
> You might prefer adding an explicit NOT NULL on both "client" and "salesman"
> columns.
> There is an historical reason why SQLite accepts NULL for primary key
> column(s).
Ok, thanks for the hint, I didn't know that either. But it is a very odd
behavior, because PRIMARY KEY per definition do
"integer primary key"s cannot contain a null since they're an alias for the
rowid. So when you insert a null into them they act similar to autoincrement
and automatically fill it in with an unused id. (Current implementation is 1
more than the _current_ highest rowid. Subject to change)
If you
Actually, I take that back...
sqlite> select * from TheTable;
1|Test
2|Test2
3|TestNull1
4|TestNull2
5|TestNull3
So the inserting of NULL in a primary key (Single instance maybe?) will
insert the new rowid.
Try running a SELECT against your table and see what kind of results you're
obtaining.
NULL is a special thing. It's never considered unique.
SQLite version 3.20.0 2017-08-01 13:24:15
Enter ".help" for usage hints.
Connected to a transient in-memory database.
Use ".open FILENAME" to reopen on a persistent database.
sqlite> create table TheTable (ID Integer, Info Text, PRIMARY KEY (
On 18 Jul 2019, at 5:02pm, Alexandre Billon wrote:
> INSERT INTO sales ("client", "salesman", "revenue")
> VALUES ('C1', NULL, 10.0);
The value NULL in SQLite means 'value unknown'. It is a special case. If you
compare two NULLs SQLite will act as if those values are different. T
> Le 18 juil. 2019 à 18:05, J. King a écrit :
>
>> Hello,
>>
>> I have created a table.
>>
>> CREATE TABLE "sales" (
>> "client"TEXT,
>> "salesman" TEXT,
>> "revenue" REAL,
>> PRIMARY KEY("client","salesman")
>> );
On 2019-07-18 12:02:18, "Alexandre Billon" wrote:
Hello,
I have created a table.
CREATE TABLE "sales" (
"client" TEXT,
"salesman"TEXT,
"revenue" REAL,
PRIMARY KEY("client","salesman")
);
I can run
Hello,
I have created a table.
CREATE TABLE "sales" (
"client"TEXT,
"salesman" TEXT,
"revenue" REAL,
PRIMARY KEY("client","salesman")
);
I can run the query below mutliple times without any error
Thanks for the response. Just to clarify, this is separate from the
`warning "gethostuuid() is disabled."` exuded from the else portion of the
conditional (when targeting iOS). When targeting UIKit for macOS, the
conditional gets into the if portion because TARGET_OS_UIKITFORMAC is not
included
I apologize in advance if this is the wrong place to report bugs with the
SQLite Android bindings, but I couldn’t figure out how to file a ticket on that
subsite (https://sqlite.org/android/) and didn’t see any contact information
there, so I figured I’d try here.
Query performance, particularl
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