Insert single into DB table by not using structure as data holder - abap

Is there a way to insert single record in db table without using structure as data holder.
I was thinking something like
INSERT INTO table(filed1, field2) VALUES (value1, value2).
Is something like this possible in abap? thx

No, this is not possible because you can't specify individual target fields with OpenSQL INSERT statements. You might be able to work around the need for a temporary structure on the right-hand side by using a VALUE type( ... ) operator, but I haven't tried that yet.

You should try to create a structure dynamically.
using CL_ABAP_STRUCTDESCR=>CREATE, specifying a list of components (list of column) and their types, you get dynamically a description of your structure that you can use to create a data reference.
Quick pseudo-code:
DATA coldescr TYPE REF TO cl_abap_structdescr.
DATA cols TYPE REF TO data.
FIELD-SYMBOLS <cols> TYPE any.
coldescr = cl_abap_structdescr=>create( ).
CREATE DATA cols TYPE HANDLE coldescr.
ASSIGN cols->* TO <cols>.
You can use <cols> in you insert select stmt.

Related

Get SRID of geometry column in exasol (ST_SRID equivalent)

It seems that there is no ST_SRID function in exasol like in other DBMS: SELECT ST_SRID(geom) FROM sampletable
Is there an efficient workaround to determine the SRID of a geometry column? So far I only had success in parsing the COLUMN_TYPE string from EXA_USER_COLUMNS of the table containing the geometry column, which seems a bit clumsy...
There is no specific function for this in Exasol.
Besides using EXA_USER_COLUMNS you can also use TYPEOF if you are using Exasol 7.1. This is a scalar function that returns the data type of it's argument.
For example:
create or replace table t(a geometry, b geometry(1), c geometry(2));
insert into t values (null,null,null);
select regexp_substr(typeof(a), '[\d]*'), regexp_substr(typeof(b), '[\d]*'),regexp_substr(typeof(c), '[\d]*') from t;

Create table using a variable name in the BigQuery UI

I am trying to write a BigQuery script that I can store as a procedure, I would like one of the arguments I pass to be used in the table name that is written out by the script, for example:
DECLARE id STRING;
SET id = '123';
CREATE OR REPLACE TABLE test.id AS(
SELECT * FROM dataset.table
)
However, in this example the table is created with the name id rather than the value of the "id" variable, 123. Is there any way I can dynamically create a table using the value of a declared variable in the BigQuery UI?
Why not just use Execute Immediate with concat if you know the table schema?
EXECUTE IMMEDIATE CONCAT('CREATE TABLE `', id, '` (column_name STRING)');
So far we have officially announced BigQuery scripting document, which is still in Beta phase, leveraging usage of dynamic parameters (variables) as a placeholders for values in SQL queries . However, according to Parameterized queries in BigQuery documentation, query parameters can't be used for SQL object identifiers:
Parameters cannot be used as substitutes for identifiers, column
names, table names, or other parts of the query.
Maybe you can use a wildcard table. You would create a wildcard table with all subtables you want to query and use the WHERE clause to select any subtable you want. Just be careful, the tables must have the same schema.

PLSQL - create type dynamically using function

I would like to implement something like the following pseudo-code. Let say I have table named T_TMP_TABLE with column 'hour', 'day', and 'year'. The table name is used as an input parameter for create_types_fn function. Let's assume that I can get a list of column names and store it to column_name_array. Now, I need to create "custom type" using those column names. The reason is that the function will return table as an output, and the columns of the returned table would be the same ('hour', 'day', and 'year')
Briefly speaking, I have a table and I need output as table-format with same column names.
Am I able to do this? any suggestion or recommendation would be much appreciated!!
CREATE OR REPLACE FUNCTION create_types_fn (table_name in varchar2)
....
begin
array column_name_array = get_column_name_in_array_by_table_name(table_name)
CREATE OR REPLACE TYPE my_type AS OBJECT (
column_name_array(0) NUMBER,
column_name_array(1) NUMBER,
column_name_array(2) VARCHAR2(30)
);
CREATE OR REPLACE type my_table AS TABLE OF my_type ;
select * bulk collect into my_table ;
end
EDIT
Here is what I am trying to do
I am trying to compare two tables and return rows if there are any difference. So, I think the output should be table-format. Since every table has different column names, I think it would be nice if I can make generic function..
If you are trying to compare the data in two different tables, you would almost certainly want to use the dbms_comparison package rather than writing your own. That populates a generic structure rather than creating new types for each table.

PostgreSQL - best way to return an array of key-value pairs

I'm trying to select a number of fields, one of which needs to be an array with each element of the array containing two values. Each array item needs to contain a name (character varying) and an ID (numeric). I know how to return an array of single values (using the ARRAY keyword) but I'm unsure of how to return an array of an object which in itself contains two values.
The query is something like
SELECT
t.field1,
t.field2,
ARRAY(--with each element containing two values i.e. {'TheName', 1 })
FROM MyTable t
I read that one way to do this is by selecting the values into a type and then creating an array of that type. Problem is, the rest of the function is already returning a type (which means I would then have nested types - is that OK? If so, how would you read this data back in application code - i.e. with a .Net data provider like NPGSQL?)
Any help is much appreciated.
ARRAYs can only hold elements of the same type
Your example displays a text and an integer value (no single quotes around 1). It is generally impossible to mix types in an array. To get those values into an array you have to create a composite type and then form an ARRAY of that composite type like you already mentioned yourself.
Alternatively you can use the data types json in Postgres 9.2+, jsonb in Postgres 9.4+ or hstore for key-value pairs.
Of course, you can cast the integer to text, and work with a two-dimensional text array. Consider the two syntax variants for a array input in the demo below and consult the manual on array input.
There is a limitation to overcome. If you try to aggregate an ARRAY (build from key and value) into a two-dimensional array, the aggregate function array_agg() or the ARRAY constructor error out:
ERROR: could not find array type for data type text[]
There are ways around it, though.
Aggregate key-value pairs into a 2-dimensional array
PostgreSQL 9.1 with standard_conforming_strings= on:
CREATE TEMP TABLE tbl(
id int
,txt text
,txtarr text[]
);
The column txtarr is just there to demonstrate syntax variants in the INSERT command. The third row is spiked with meta-characters:
INSERT INTO tbl VALUES
(1, 'foo', '{{1,foo1},{2,bar1},{3,baz1}}')
,(2, 'bar', ARRAY[['1','foo2'],['2','bar2'],['3','baz2']])
,(3, '}b",a{r''', '{{1,foo3},{2,bar3},{3,baz3}}'); -- txt has meta-characters
SELECT * FROM tbl;
Simple case: aggregate two integer (I use the same twice) into a two-dimensional int array:
Update: Better with custom aggregate function
With the polymorphic type anyarray it works for all base types:
CREATE AGGREGATE array_agg_mult (anyarray) (
SFUNC = array_cat
,STYPE = anyarray
,INITCOND = '{}'
);
Call:
SELECT array_agg_mult(ARRAY[ARRAY[id,id]]) AS x -- for int
,array_agg_mult(ARRAY[ARRAY[id::text,txt]]) AS y -- or text
FROM tbl;
Note the additional ARRAY[] layer to make it a multidimensional array.
Update for Postgres 9.5+
Postgres now ships a variant of array_agg() accepting array input and you can replace my custom function from above with this:
The manual:
array_agg(expression)
...
input arrays concatenated into array of one
higher dimension (inputs must all have same dimensionality, and cannot
be empty or NULL)
I suspect that without having more knowledge of your application I'm not going to be able to get you all the way to the result you need. But we can get pretty far. For starters, there is the ROW function:
# SELECT 'foo', ROW(3, 'Bob');
?column? | row
----------+---------
foo | (3,Bob)
(1 row)
So that right there lets you bundle a whole row into a cell. You could also make things more explicit by making a type for it:
# CREATE TYPE person(id INTEGER, name VARCHAR);
CREATE TYPE
# SELECT now(), row(3, 'Bob')::person;
now | row
-------------------------------+---------
2012-02-03 10:46:13.279512-07 | (3,Bob)
(1 row)
Incidentally, whenever you make a table, PostgreSQL makes a type of the same name, so if you already have a table like this you also have a type. For example:
# DROP TYPE person;
DROP TYPE
# CREATE TABLE people (id SERIAL, name VARCHAR);
NOTICE: CREATE TABLE will create implicit sequence "people_id_seq" for serial column "people.id"
CREATE TABLE
# SELECT 'foo', row(3, 'Bob')::people;
?column? | row
----------+---------
foo | (3,Bob)
(1 row)
See in the third query there I used people just like a type.
Now this is not likely to be as much help as you'd think for two reasons:
I can't find any convenient syntax for pulling data out of the nested row.
I may be missing something, but I just don't see many people using this syntax. The only example I see in the documentation is a function taking a row value as an argument and doing something with it. I don't see an example of pulling the row out of the cell and querying against parts of it. It seems like you can package the data up this way, but it's hard to deconstruct after that. You'll wind up having to make a lot of stored procedures.
Your language's PostgreSQL driver may not be able to handle row-valued data nested in a row.
I can't speak for NPGSQL, but since this is a very PostgreSQL-specific feature you're not going to find support for it in libraries that support other databases. For example, Hibernate isn't going to be able to handle fetching an object stored as a cell value in a row. I'm not even sure the JDBC would be able to give Hibernate the information usefully, so the problem could go quite deep.
So, what you're doing here is feasible provided you can live without a lot of the niceties. I would recommend against pursuing it though, because it's going to be an uphill battle the whole way, unless I'm really misinformed.
A simple way without hstore
SELECT
jsonb_agg(to_jsonb (t))
FROM (
SELECT
unnest(ARRAY ['foo', 'bar', 'baz']) AS table_name
) t
>>> [{"table_name": "foo"}, {"table_name": "bar"}, {"table_name": "baz"}]

how to convert result of an select sql query into a new table in ms access

how to convert result of an select sql query into a new table in msaccess ?
You can use sub queries
SELECT a,b,c INTO NewTable
FROM (SELECT a,b,c
FROM TheTable
WHERE a Is Null)
Like so:
SELECT *
INTO NewTable
FROM OldTable
First, create a table with the required keys, constraints, domain checking, references, etc. Then use an INSERT INTO..SELECT construct to populate it.
Do not be tempted by SELECT..INTO..FROM constructs. The resulting table will have no keys, therefore will not actually be a table at all. Better to start with a proper table then add the data e.g. it will be easier to trap bad data.
For an example of how things can go wrong with an SELECT..INTO clause: it can result in a column that includes the NULL value and while after the event you can change the column to NOT NULL the engine will not replace the NULLs, therefore you will end up with a NOT NULL column containing NULLs!
Also consider creating a 'viewed' table e.g. using CREATE VIEW SQL DDL rather than a base table.
If you want to do it through the user interface, you can also:
A) Create and test the select query. Save it.
B) Create a make table query. When asked what tables to show, select the query tab and your saved query.
C) Tell it the name of the table you want to create.
D) Go make coffee (depending on taste and size of table)
Select *
Into newtable
From somequery