In my project I'm using Doctrine doctrine 2.5.4/postgres 9.5. I'm trying to add a jsonb field using YAML:
fields:
obj: json_array
This gets interpreted as a json column type (and not jsonb). The specification notes about picking up json or jsonb:
Chosen if the column definition contains the jsonb option inside the platformOptions attribute array and is set to true.
But platformOptions doesn't seem to work (tried to add it below obj, at the top... with no success). How can I add a jsonb field?
This is supported by doctrine/dbal v2.6+ (it requires PHP 7.1). All you need to do is use json_array and set options={"jsonb"=true} I tested this on doctrine/dbal v2.6.3
This is what it looks like in PHP format:
/**
* #ORM\Column(type="json_array",nullable=true,options={"jsonb"=true})
*/
private $details;
and it creates a query such as (for an existing table):
ALTER TABLE mytable ADD details JSONB NOT NULL;
More details about type mapping can be found at Doctrine mapping matrix.
Use boldtrn/jsonb-bundle, it provides a jsonb doctrine type as well as custom functions to access the special operators provided by the PostgreSQL jsonb data type.
Related
I'm trying to create a index, like this one:
CREATE INDEX example1_gpx ON example1 USING GIST (geography(geomcol));
Using EF codefirst, I did this on codefirst:
builder.HasIndex(x => new
{
x.GeoLocation
})
.HasMethod("GIST");
but I can't specify that it's a column of type geography.
How I can create this index using CodeFirst ?
Your index above seems to apply a geography() conversion to a geometry column; if so, it's an expression index (as opposed to a simple index over a column). The Npgsql EF Core provider doesn't currently support modeling expression indexes (see this issue), but you can always use raw SQL to create the index in migrations.
However, I'd recommend thinking why you're converting a geometry column into geography in an expression index; you may want to consider making your column geography instead. Another option is to have an additional generated column of type geography alongside the geometry column.
I have created a model in Django.
class MyModel(models.Model):
features = TextField(blank=True, default='')
There are several possible ways to store the data in the feature field. Some examples below.
feature1;feature2
feature1, feature2
feature1,feature2
And so on. I created a GIN index for that field using migrations.RunSQL() (thanks to the following answer). The postgreSQL command looks as follows
CREATE INDEX features_search_idx ON "mymodel" USING gin (regexp_split_to_array("mymodel"."features", '[,;\\s]+'));
Now I need to check the size of the created index in my database. I tried to do it with the following commands
SELECT pg_size_pretty (pg_indexes_size("mymodel"."features_search_idx"));
SELECT pg_size_pretty(pg_indexes_size("features_search_idx")) FROM "mymodel";
The latter one failed with ERROR: column "features_search_idx" does not exist and the former one failed with ERROR: missing FROM-clause entry for table "mymodel".
How can I check the index size?
pg_indexes_size takes an argument of type regclass, that is an object ID that is represented as a string that is the object name. So if you don't supply an object ID, you have to supply a string (single quotes) that is the name of the table:
SELECT pg_size_pretty (pg_indexes_size('mymodel.features_search_idx'));
I have a JSONB column in PostgreSQL database like {lat: value, lon: value}. I want to change any specific value at a time eg. lat, but I am not sure how I can achieve this using bookshelf.js or knex.js. I tried using jsonb_set() method specified in Postgres documentation but I am not sure if I used that correctly. Can somebody please suggest me how can I do this? or what is the correct syntax to do this? Thanks.
AFAIK only knex based thing that supports writing to and extracting data from postgresql jsonb columns is objection.js ORM.
With plain knex you need to use raw to write references:
knex('table').update({
jsonbColumn: knex.raw(`jsonb_set(??, '{lat}', ?)`, ['jsonbColumn', newLatValue])
})
You can check generated SQL here https://runkit.com/embed/44ifdhzxejf1
Originally answered in: https://github.com/tgriesser/knex/issues/2264
More examples how to use jsonb_set with knex can be found in following answers
How to update a jsonb column's field in PostgreSQL?
What is the best way to use PostgreSQL JSON types with NodeJS
Jsonb field update using knex.js
return knex("tablename").update({
jsonbkey: knex.raw(`
jsonb_set(jsonbkey, '{city}','"Ayodhya"')
`)
}).where({"id" :2020})
The jsonbkey will be the column name, where the datatype is jsonb.
The tablename is the name of your table.
The city is the object key.
If there is multiple level of object then you can use dot. Like '{city.id}'
let result = await db().raw(`UPDATE widget
SET name = ?,
jsonCol= jsonCol::jsonb || ?::jsonb
WHERE id = ?`,
[name, JSON.stringify(newJsonData), id);
this knex query helps to update any json column by overriding specific keys in the value supplied to the right hand side of || operator. DO NOT forget to typecast the values with ::jsonb
Can we expect native support for the jsonb field when saving poco objects into a field? (and query for fields inside the jsonb field using the correct postgresql syntax)?
Thanks
I am working with DB2 Universal database having lots of tables with columns of datatype CHARACTER. Length of these columns is variable (greater than 1 e.g. 18). As i execute a Native query using JPA it selects only first character of the column. Seems CHARACTER datatype is mapped to Java Character.
How can i get full contents in DB column. I can not change the database bening on Vendor side. Please note i need to do it both ways, i.e. :
Using JPQL ( is attribute columnDefinition can work in this case)
Using native DB query (no pojo is used in this case and i have no control over datatypes)
i am using Hibernate implementation of JPA provided by spring.
If these columns are actually common in your database, you can customize a dialect used by Hibernate. See comments to HHH-2304.
I was able to cast the column to VARCHAR to produce padded String results from createNativeQuery:
select VARCHAR(char_col) from schema.tablename where id=:id