Question

我的表在sql server上看起来像这样

void gener_random(int size, int **values) {
    // Dereference the pointer to the pointer, to work
    // on the variable declared in `main()' (the original pointer)
    *values = malloc(size * sizeof(values));
    if (*values == NULL) // Perhaps reutnr `int' and error code
        return;
    for(int i = 0; i < size; i++)
        (*values)[i] = rand(); 
}

WordId和word正在与存储过程一起传递，如果wordId已经存在于表中，我需要检查我的存储过程，并且只有当wordId不存在时我才需要执行插入声明。

Answer 1

首先，在wordid上创建一个唯一索引：

create unique index unq_t_wordid on t(wordid);

这将保护数据并确保不会插入重复数据。

其次，在任何特定的insert中，您可以在插入时进行检查：

insert into t (wordid, word)
    select wordid, word
    from (. . .) x
    where not exists (select 1 from t where t.wordid = x.wordid);

当然，最终，我建议您将wordid定义为标识列，但实际插入该值可能还有其他原因。

Answer 2

试试这个：

CREATE PROCEDURE Your_ProcName(@wordId INT,@word VARCHAR(20))
AS
BEGIN
    IF NOT EXISTS(SELECT 1 FROM Your_Table WHERE wordId = @wordId)
    BEGIN
        INSERT INTO Your_Table (wordid, word)
        SELECT @wordId, @word
    END
    ELSE
    BEGIN
        PRINT 'Values already Exists'
    END
END

Answer 3

CREATE PROCEDURE Your_ProcName(@wordId INT,@word VARCHAR(20))
AS
BEGIN
    Declare @nCount int;
    SET NOCOUNT ON
     Select @nCount = Count(*) from Your_Table WHERE wordId = @wordId
   BEGIN TRY
        DECLARE @ErrorMessage1 varchar(4000)    
    IF (@numRec > 0)
        BEGIN
            SET @ErrorMessage1 = 'ERROR: A wordId is already exists.'
            RAISERROR (@ErrorMessage1, 16, 1)
        END
        IF @numRec = 0
            BEGIN TRANSACTION
            INSERT INTO Your_Table (wordid, word)
            SELECT @wordId, @word
        COMMIT

    END TRY
    BEGIN CATCH
        SELECT
            @ErrorMessage1 AS 'ERROR_MESSAGE'
        RAISERROR (@ErrorMessage1, 16, 1)
    END CATCH




END
GO

如果条目不存在，如何将条目插入表中

3 个答案: