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C# 如何确定是否已在SQLite表上创建索引?_C#_Sqlite - Fatal编程技术网

C# 如何确定是否已在SQLite表上创建索引?

C# 如何确定是否已在SQLite表上创建索引?,c#,sqlite,C#,Sqlite,我正在使用此代码创建和索引。我意识到,如果索引已经存在,它将不会创建它,但是有人能告诉我,有没有一种方法可以让我知道索引是否已经创建 db2.Execute("CREATE UNIQUE INDEX IF NOT EXISTS idx_History on History(YYMMDD,Mode,Quiz,CC,Deck)"); 您可以使用内部sqlite\u master表查询索引: var result = await conn.ExecuteScalarAsync<int>(

我正在使用此代码创建和索引。我意识到,如果索引已经存在,它将不会创建它,但是有人能告诉我,有没有一种方法可以让我知道索引是否已经创建

db2.Execute("CREATE UNIQUE INDEX IF NOT EXISTS idx_History on History(YYMMDD,Mode,Quiz,CC,Deck)");

您可以使用内部
sqlite\u master
表查询索引:

var result = await conn.ExecuteScalarAsync<int>("SELECT count(*) FROM sqlite_master WHERE type='index' and name=?;", new string[] { "someIndexName" });
if (result == 1)
{
   ~~~
var result=wait conn.ExecuteScalarAsync(“从sqlite_master中选择count(*),其中type='index'和name=?;”,新字符串[]{“someIndexName”});
如果(结果==1)
{
~~~