How the SQLite database determines whether a table or field exists

1. Determine if the table name exists:

SELECT * FROM Sqlite_master

The table structure of the Sqlite_master is as follows:

Type |name |tbl_name |rootpage |sql

Model query results;

=============
Type>>table
Name>>android_metadata
Tbl_name>>android_metadata
Rootpage>>3
Sql>>create TABLE android_metadata (locale TEXT)
=============
Type>>table
Name>>talkvo
Tbl_name>>talkvo
Rootpage>>4
Sql>>create TABLE talkvo (content text,videopath text,img text,name text,issend blob,isplaying Integer , _id integer PRIMARY KEY)

2. Determine whether the field exists

PRAGMA Table_info ([Talkvo])

Must be capitalized, structured as follows:

CID | name | Type | Notnull |  Dflt_value | Pk

Model query results;

PRAGMA Table_info ([Talkvo])
=============
Cid>>0
Name>>content
Type>>text
Notnull>>0
Dflt_value>>null
Pk>>0
=============
Cid>>1
1name>>videopath
Type>>text
Notnull>>0
Dflt_value>>null
Pk>>0
=============
Cid>>2
Name>>img
Type>>text
Notnull>>0
Dflt_value>>null
Pk>>0
=============
Cid>>3
Name>>name
Type>>text
Notnull>>0
Dflt_value>>null
Pk>>0
=============
Cid>>4
Name>>issend
Type>>blob
Notnull>>0
Dflt_value>>null
Pk>>0
=============
Cid>>5
Name>>isplaying
Type>>integer
Notnull>>0
Dflt_value>>null
Pk>>0
=============
Cid>>6
Name>>uid
Type>>integer
Notnull>>0
Dflt_value>>null
Pk>>0
=============
Cid>>7
name>>_id
Type>>integer
Notnull>>0
Dflt_value>>null
Pk>>1