121 lines
2.4 KiB
Plaintext
121 lines
2.4 KiB
Plaintext
--
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-- TEXT
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--
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SELECT text 'this is a text string' = text 'this is a text string' AS true;
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true
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------
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t
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(1 row)
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SELECT text 'this is a text string' = text 'this is a text strin' AS false;
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false
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-------
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f
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(1 row)
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CREATE TABLE TEXT_TBL (f1 text);
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INSERT INTO TEXT_TBL VALUES ('doh!');
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INSERT INTO TEXT_TBL VALUES ('hi de ho neighbor');
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SELECT '' AS two, * FROM TEXT_TBL;
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two | f1
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-----+-------------------
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| doh!
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| hi de ho neighbor
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(2 rows)
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-- As of 8.3 we have removed most implicit casts to text, so that for example
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-- this no longer works:
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select length(42);
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ERROR: function length(integer) does not exist
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LINE 1: select length(42);
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^
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HINT: No function matches the given name and argument types. You might need to add explicit type casts.
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-- But as a special exception for usability's sake, we still allow implicit
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-- casting to text in concatenations, so long as the other input is text or
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-- an unknown literal. So these work:
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select 'four: '::text || 2+2;
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?column?
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----------
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four: 4
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(1 row)
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select 'four: ' || 2+2;
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?column?
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----------
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four: 4
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(1 row)
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-- but not this:
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select 3 || 4.0;
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ERROR: operator does not exist: integer || numeric
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LINE 1: select 3 || 4.0;
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^
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HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.
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/*
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* string functions
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*/
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select concat('one');
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concat
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--------
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one
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(1 row)
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select concat(1,2,3,'hello',true, false, to_date('20100309','YYYYMMDD'));
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concat
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----------------------
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123hellotf03-09-2010
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(1 row)
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select concat_ws('#','one');
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concat_ws
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-----------
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one
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(1 row)
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select concat_ws('#',1,2,3,'hello',true, false, to_date('20100309','YYYYMMDD'));
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concat_ws
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----------------------------
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1#2#3#hello#t#f#03-09-2010
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(1 row)
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select concat_ws(',',10,20,null,30);
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concat_ws
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-----------
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10,20,30
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(1 row)
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select concat_ws('',10,20,null,30);
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concat_ws
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-----------
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102030
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(1 row)
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select concat_ws(NULL,10,20,null,30) is null;
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?column?
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----------
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t
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(1 row)
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select reverse('abcde');
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reverse
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---------
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edcba
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(1 row)
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select i, left('ahoj', i), right('ahoj', i) from generate_series(-5, 5) t(i) order by i;
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i | left | right
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----+------+-------
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-5 | |
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-4 | |
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-3 | a | j
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-2 | ah | oj
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-1 | aho | hoj
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0 | |
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1 | a | j
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2 | ah | oj
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3 | aho | hoj
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4 | ahoj | ahoj
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5 | ahoj | ahoj
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(11 rows)
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