SQLiteDataBase对象的query()接口：
public Cursor query (String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy,String limit)
Query the given table, returning a Cursor
Parameters
| table | The table name to compile the query against.(要查询的表名.) |
|---|---|
| columns | A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn‘t going to be used.(想要显示的列，若为空则返回所有列，不建议设置为空，如果不是返回所有列) |
| selection | A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given table.(where子句，声明要返回的行的要求，如果为空则返回表的所有行。) |
| selectionArgs |
You may include ?s in selection, which will be replaced by the values from selectionArgs, in order that they appear in the selection. The values will be bound as Strings.( |
| groupBy | A filter declaring how to group rows, formatted as an SQL GROUP BY clause (excluding the GROUP BY itself). Passing null will cause the rows to not be grouped.(分组方式，若为空则不分组.) |
| having | A filter declare which row groups to include in the cursor, if row grouping is being used, formatted as an SQL HAVING clause (excluding the HAVING itself). Passing null will cause all row groups to be included, and is required when row grouping is not being used.(having条件，若为空则返回全部（不建议）) |
| orderBy | How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.(排序方式，为空则为默认排序方式) |
| limit | Limits the number of rows returned by the query, formatted as LIMIT clause. Passing null denotes no LIMIT clause.(限制返回的记录的条数，为空则不限制) |
示例：ContentValues
cv = new ContentValues();String[]
args = {String.valueOf("a")};
query("user",
new String[] {
SQLiteDataBase对象的insert()接口：
public long (String table, String nullColumnHack, ContentValues values)
Convenience method for inserting a row into the database.
Parameters
| table | the table to insert the row into(要插入数据的表的名称) |
|---|---|
| nullColumnHack |
optional; may be null. SQL doesn‘t allow inserting a completely empty row without naming at least one column name. If your provided valuesis
empty, no column names are known and an empty row can‘t be inserted. If not set to null, the nullColumnHack values |
| values | this map contains the initial column values for the row. The keys should be the column names and the values the column values(一个ContentValues对象，类似一个map.通过键值对的形式存储值。) |
Returns
- the row ID of the newly inserted row, or -1 if an error occurred
示例：ContentValues
cv = new ContentValues();cv.put("username", "a");
cv.put("password", "b");
insert("user", null,
cv);
SQLiteDataBase对象的update()接口：
public int (String table, ContentValues values, String whereClause, String[] whereArgs)
Convenience method for updating rows in the database.
Parameters
| table | the table to update in(要更新的表名) |
|---|---|
| values | a map from column names to new column values. null is a valid value that will be translated to NULL.(一个ContentValues对象，类似一个map.通过键值对的形式存储值。) |
|
whereClause whereArgs |
the optional WHERE clause to apply when updating. Passing null will update all rows.(可选的where语句) the group of args to deal with(whereClause语句中表达式的？占位参数列表) |
Returns
- the number of rows affected
ContentValues
cv = new ContentValues();cv.put("username", "c");
cv.put("password", "d");
String[] args = {String.valueOf("a")};
update("user",
cv, "username=?",args)
SQLiteDataBase对象的delete()接口：
public int (String table, String whereClause, String[] whereArgs)
Convenience method for deleting rows in the database.
Parameters
| table | the table to delete from |
|---|---|
|
whereClause whereArgs |
the optional WHERE clause to apply when deleting. Passing null will delete all rows.(可选的where语句) the optional WHERE clause to apply when updating. Passing null will update all rows.(whereClause语句中表达式的？占位参数列表) |
Returns
- the number of rows affected if a whereClause is passed in, 0 otherwise. To remove all rows and get a count pass "1" as the whereClause.
示例：ContentValues
cv = new ContentValues();
String[] args = {String.valueOf("c")};
delete("user", "username=?",
args);
SQLiteDatabase中query、insert、update、delete方法参数说明,布布扣,bubuko.com