I have inserted some test data like below:
INSERT INTO tblDataInfo (lookupkey, lookupvalue, scope)
VALUES ('diskname', '/dev/sdb', 'common')
yours sincerely
I wanted to query this data and like to obtain the query output in JSON format.
I have used the query
select lookupvalue as 'disk.name'
from tblDataInfo
where lookupkey = 'diskname' FOR JSON PATH;
This query returns
[{"disk":{"name":"\/dev\/sdb"}}]
which is escaping all my forward slashes (/) using the escape character (\). How can I have my output not to put escape-character (\)?
This query returns result that you need:
select json_query ('{"name":"' + lookupvalue + '"}') as 'disk'
from tblDataInfo
where lookupkey = 'diskname'
for json path;
Related
I need to clean JSON data that could look like:
{
"reference":"0000010-CAJ",
"product_code":"00000-10",
"var_name":"CAJ-1",
"doc_date":"2020-02-09T21:01:01-05:00",
"due_date":"2020-03-10T21:01:01-05:00",
}
However, this is just one of many other possibilities (is for a log aggregation that gets data from many sources).
I need to replace "-" with "_", but without break the dates like "2020-03-10T21:01:01-05:00", so can't simply cast to string and do a replace. I wonder if exist an equivalent of:
for (k,v) in json:
if is_text(v):
v = replace(...)
You can check with a regex if the value looks like a timestamp:
update the_table
set the_column = (select
jsonb_object_agg(
key,
case
when value ~ '^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}.*' then value
else replace(value, '-', '_')
end)
from jsonb_each_text(the_column) as t(key, value))
This iterates over all key/value pairs in the JSON column (using jsonb_each_text()) and assembles all of them back into a JSON again (using jsonb_object_agg()). Values that look like a timestamp are left unchanged, for all others, the - is replaced with a _.
First week having to deal with a MYSQL database and JSON field types and I cannot seem to figure out why values are encoded automatically and then returned in encoded format.
Given the following SQL
-- create a multiline string with a tab example
SET #str ="Line One
Line 2 Tabbed out
Line 3";
-- encode it
SET #j = JSON_OBJECT("str", #str);
-- extract the value by name
SET #strOut = JSON_EXTRACT(#J, "$.str");
-- show the object and attribute value.
SELECT #j, #strOut;
You end up with what appears to be a full formed JSON object with a single attribute encoded.
#j = {"str": "Line One\n\tLine 2\tTabbed out\n\tLine 3"}
but using JSON_EXTRACT to get the attribute value I get the encoded version including outer quotes.
#strOut = "Line One\n\tLine 2\tTabbed out\n\tLine 3"
I would expect to get my original string with the \n \t all unescaped to the original values and no outer quotes. as such
Line One
Line 2 Tabbed out
Line 3
I can't seem to find any JSON_DECODE or JSON_UNESCAPE or similar functions.
I did find a JSON_ESCAPE() function but that appears to be used to manually build a JSON object structure in a string.
What am I missing to extract the values to the original format?
I like to use handy operator ->> for this.
It was introduced in MySQL 5.7.13, and basically combines JSON_EXTRACT() and JSON_UNQUOTE():
SET #strOut = #J ->> '$.str';
You are looking for the JSON_UNQUOTE function
SET #strOut = JSON_UNQUOTE( JSON_EXTRACT(#J, "$.str") );
The result of JSON_EXTRACT() is intentionally a JSON document, not a string.
A JSON document may be:
An object enclosed in { }
An array enclosed in [ ]
A scalar string value enclosed in " "
A scalar number or boolean value
A null — but this is not an SQL NULL, it's a JSON null. This leads to confusing cases because you can extract a JSON field whose JSON value is null, and yet in an SQL expression, this fails IS NULL tests, and it also fails to be equal to an SQL string 'null'. Because it's a JSON type, not a scalar type.
I have a server log, it continuously records json values without any delimiter, such as:
{"a":1}{"b",2}{"a":2}{"c":{\"qwe\":\"asd\"},"d":"ert"}{"e":12}....
I want to extract each element and put them into rows like:
{"a":1}
{"b",2}
{"a":2}
{"c":{\"qwe\":\"asd\"},"d":"ert"}
{"e":12}..
The log lacks delimiter and comprises nested json, so I cannot use
split function...How to achieve this...
One option would be to split on }{ character and get the elements using posexplode. Positions are only needed to concatenate properly for the first and last elements.
select case when pos = 0 then concat(split_str,'}')
when pos = max(pos) over(partition by str) then concat('{',split_str)
else concat('{',split_str,'}') end as res
from tbl
lateral view posexplode(split(str,'\\}\\{')) t as pos,split_str
Note the result will be a string.
I'd like to CONCAT two column value into one string in string in JSON format. However I have problem with the quote and double quote in the query. How do I fix my query so it success produce the expected result?
$concat = "CONCAT('{"CODE":"pm_r.CODE","NAME":"pm_r.NAME"}') AS `JSON`"
$query = $this->db->query(
'SELECT pm_r.ID_REQUIREMENT, '.$concat.'FROM `pm_requirement` `pm_r`'
);
The expected out should be:
ID_REQUIREMENT JSON
ID001 {"CODE":"001","NAME":"Shane"}
To avoid quoting clashes, a solution is to use a php HEREDOC string.
I also fixed you CONCAT, where the names of the column to concatenate should be separated from the fixed parts of the string.
$query = $this->db->query(<<<EOT
SELECT
pm_r.ID_REQUIREMENT,
CONCAT('{"CODE":"', pm_r.CODE, '","NAME":"', pm_r.NAME, '"}') AS `JSON`
FROM `pm_requirement` `pm_r`
EOT
);
My table has a column with a JSON string that has nested objects (so a simple REPLACE function cannot solve this problem) . For example like this: {'name':'bob', 'blob': {'foo':'bar'}, 'age': 12}. What is the easiest query to append a value to the end of the JSON string? So for the example, I want the end result to look like this: {'name':'bob', 'blob': {'foo':'bar'}, 'age': 12, 'gender': 'male'} The solution should be generic enough to work for any JSON values.
What about this
UPDATE table SET table_field1 = CONCAT(table_field1,' This will be added.');
EDIT:
I personally would have done the manipulation with a language like PHP before inserting it. Much easier. Anyway, Ok is this what you want? This should work providing your json format that is being added is in the format {'key':'value'}
UPDATE table
SET col = CONCAT_WS(",", SUBSTRING(col, 1, CHAR_LENGTH(col) - 1),SUBSTRING('newjson', 2));
I think you can use REPLACE function to achieve this
UPDATE table
SET column = REPLACE(column, '{\'name\':\'bob\', \'blob\': {\'foo\':\'bar\'}, \'age\': 12}', '{\'name\':\'bob\', \'blob\': {\'foo\':\'bar\'}, \'age\': 12, \'gender\': \'male\'}')
Take care to properly escape all quotes inside json
Upon you request of nested json, i think you can just remove last character of the string with SUBSTRING function and then append whatever you need with CONCAT
UPDATE table
SET column = CONCAT(SUBSTRING(column, 0, -1), 'newjsontoappend')
modify Jack's answer. Works perfectly even column value is empty on first update.
update table
set column_name = case when column_name is null or column_name =''
then "{'foo':'bar'}"
else CONCAT_WS(",", SUBSTRING(column_name, 1, CHAR_LENGTH(column_name) - 1),SUBSTRING("{'foo':'bar'}", 2))
end