Like select * from table whe开发者_C百科re text_field;
What would get pulled?
If you do select * from atable where text_field;
, you will get the rows where text_field='1'.
Similar to select * from atable where text_field='1';
.
I'm not sure I understand the question.
An error.
My best guess is that you want select * from table where text_field is not null
.
ceteras is right, WHERE text_field
returns true where text_field = '1' (for some obscure reason).
However, pay attention : NULL is not equal to an empty string (NULL is not even equal to NULL !). If you want to select every row where the column text_field is not empty, you would have to do something like this :
SELECT * FROM table WHERE LENGTH(text_field) > 0;
-- or
SELECT * FROM table WHERE text_field <> '';
The last query can use an index if wanted, I am not so sure about the first.
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