I want to run multiple command statements one after the other.
For example, I create a table and then drop it :-
.create table MyLogs ( Level:string, Timestamp:datetime,Message:string);
.drop table MyLogs;
When I paste the above 2 lines in the Query tab and click on execute, I get a syntax error :
๎จน
Syntax Error
A recognition error occurred.
Token: .
Line: 2, Position: 0
clientRequestId: KustoWebV2;xxxxxxxxx
I have a .kql file that contains multiple control commands that must be executed one after the other - How can I do that?
.execute database script
.execute database script <|
.create table MyLogs (Level:string, Timestamp:datetime, Message:string)
.drop table MyLogs
OperationId
CommandType
CommandText
Result
Reason
a25a49a8-91b9-46c9-9ca9-adef76573642
TableCreate
.create table MyLogs (Level:string, Timestamp:datetime, Message:string)
Completed
e016fe3a-b655-4788-8ada-2b1a085bbd7d
TableDrop
.drop table MyLogs;
Completed
Related
I'm writing a function which takes in raw data table (contains multijson telemetry data) and reformat it to a multiple cols. I use .set MyTable <| myfunction|limit 0 to create my target table based off of the function and use update policy to alert my target table.
Here is the code :
.set-or-append MyTargetTable <|
myfunction
| limit 0
.alter table MyTargetTable policy update
#'[{ "IsEnabled": true, "Source": "raw", "Query": "myfunction()", "IsTransactional": false, "PropagateIngestionProperties": false}]'
But I'm getting ingestion failures: Here is the ingestion failure message :
Failed to invoke update policy. Target Table = 'MyTargetTable', Query = '
let raw = __table("raw", 'All', 'AllButRowStore')
| where extent_id() in (guid(659e3b3c-6859-426d-9c37-003623834455));
myfunction()': Query schema does not match table schema
I double check the query schema and target table; they are the same . I'm not sure what this error means.
Also, I ran count on both the raw and mytarget tables; there are relatively large discrepancies (400 rows for My target and 2000 rows in raw table).
Any advise will be appreciated.
Generally speaking - to find the root of the mismatch between schemas, you can run something along the following lines, and filter for differences:
myfunction
| getschema
| join kind=leftouter (
table('MyTargetTable')
| getschema
) on ColumnOrdinal, ColumnType
In addition - you should make sure the output schema of the function you use in your update policy is 'stable', i.e. isn't affected by the input data
The output schema of some query plugins such as pivot() and bag_unpack() depends on the input data, and therefore it isn't recommended to use those in update policies.
I have a stored function that generates an identity name based on a set of parameters like this:
.create function
with (docstring = 'Returns the table name for the specified data log provider.')
GetTableName(param1: string, param2: string)
{
// Some string cleansing and concatenation
let tableName = strcat(system, source);
tableName
}
I want to use this function to create a table. Tried the following options with no success:
.create table GetTableName('value1', 'value2') (Timestamp: datetime)
.create table [GetTableName('value1', 'value2')] (Timestamp: datetime)
I'm guessing the command expects the table name to be a string literal. Is there any way to accomplish this?
Control commands that create tables cannot include query execution (and vise versa: queries cannot run control commands).
The restriction exists for security reasons.
You can achieve the scenario using client code and having two calls:
1) Derive table name
2) Generate table create command and send it to the server.
I am trying to move form DynamoDB to DynamoDB2 to use tables with global secondary indices. I need to create a table and then batch-write items into it. Here's a block of tets code:
from boto.dynamodb2.fields import HashKey, RangeKey, GlobalAllIndex
from boto.dynamodb2.layer1 import DynamoDBConnection
from boto.dynamodb2.table import Table
from boto.dynamodb2.items import Item
import boto
conn = DynamoDBConnection(aws_access_key_id=<MYID>,aws_secret_access_key=<MYKEY>)
tables = conn.list_tables()
table_name = 'myTable001'
if table_name not in tables['TableNames']:
Table.create(table_name, schema=[HashKey('firstKey')], throughput={'read': 5, 'write': 2}, global_indexes=[
GlobalAllIndex('secondKeyIndex', parts=[HashKey('secondKey')], throughput={'read': 5, 'write': 3})], connection=conn)
table = Table(table_name, connection=conn)
with table.batch_write() as batch:
batch.put_item(data={'firstKey': 'fk01', 'secondKey':'sk001', 'message': '{"firstKey":"fk01", "secondKey":"sk001", "comments": "fk01-sk001"}'})
# ...
batch.put_item(data={'firstKey': 'fk74', 'secondKey':'sk112', 'message': '{"firstKey":"fk74", "secondKey":"sk012", "comments": "fk74-sk012"}'})
When I run this code for the 1st time with a new value of table_name, I get the following error at the last line of the block:
boto.exception.JSONResponseError: JSONResponseError: 400 Bad Request
{u'message': u'Requested resource not found', u'__type': u'com.amazonaws.dynamodb.v20120810#ResourceNotFoundException'}
When I run it one more time, it get executed fine. I suspect that the reason is simply that the table is still being created when I run it for the first time. How do I check for table's status in DDB2? In DDB I used table.status but this does not seem to be available in DDB2. What should I use instead?
UPDATE: Based on final response here, the right way to extract table status is:
tdescr = conn.describe_table(tName)
print "%s" % ((tdescr['Table'])['TableStatus'])
Here are the other elements of the description dictionary:
for key in tdescr['Table'].keys():
print key
GlobalSecondaryIndexes
AttributeDefinitions
ProvisionedThroughput
TableSizeBytes
TableName
TableStatus
KeySchema
ItemCount
CreationDateTime
You can use conn.describe_table('table') to fetch the details about table & then check for the TableStatus field in the returned output.
I am executing the following query
DELETE FROM List,Tree WHERE List.CatID = Tree.CatID AND List.ID = '1' AND Tree.Cat = '332'
but I run into following error
near ",": syntax error
Correct syntax for delete statement is this
DELETE FROM table_name WHERE somecolumn=somevalue
So you cannot use 2 tables in a single delete query by separating them with a comma..
You need to do something like
DELETE something FROM table_name INNER JOIN...
You can delete only from one table at a time, and you have to rewrite the join as a subquery:
DELETE FROM List
WHERE ID = '1'
AND CatID IN (SELECT CatID
FROM Tree
WHERE Cat = '332')
I need to get column names and their tables in a SQLite database. What I need is a resultset with 2 columns: table_name | column_name.
In MySQL, I'm able to get this information with a SQL query on database INFORMATION_SCHEMA. However the SQLite offers table sqlite_master:
sqlite> create table students (id INTEGER, name TEXT);
sqlite> select * from sqlite_master;
table|students|students|2|CREATE TABLE students (id INTEGER, name TEXT)
which results a DDL construction query (CREATE TABLE) which is not helpful for me and I need to parse this to get relevant information.
I need to get list of tables and join them with columns or just get columns along with table name column. So PRAGMA table_info(TABLENAME) is not working for me since I don't have table name. I want to get all column metadata in the database.
Is there a better way to get that information as a result set by querying database?
You've basically named the solution in your question.
To get a list of tables (and views), query sqlite_master as in
SELECT name, sql FROM sqlite_master
WHERE type='table'
ORDER BY name;
(see the SQLite FAQ)
To get information about the columns in a specific table, use PRAGMA table_info(table-name); as explained in the SQLite PRAGMA documentation.
I don't know of any way to get tablename|columnname returned as the result of a single query. I don't believe SQLite supports this. Your best bet is probably to use the two methods together to return the information you're looking for - first get the list of tables using sqlite_master, then loop through them to get their columns using PRAGMA table_info().
Recent versions of SQLite allow you to select against PRAGMA results now, which makes this easy:
SELECT
m.name as table_name,
p.name as column_name
FROM
sqlite_master AS m
JOIN
pragma_table_info(m.name) AS p
ORDER BY
m.name,
p.cid
where p.cid holds the column order of the CREATE TABLE statement, zero-indexed.
David Garoutte answered this here, but this SQL should execute faster, and columns are ordered by the schema, not alphabetically.
Note that table_info also contains
type (the datatype, like integer or text),
notnull (1 if the column has a NOT NULL constraint)
dflt_value (NULL if no default value)
pk (1 if the column is the table's primary key, else 0)
RTFM: https://www.sqlite.org/pragma.html#pragma_table_info
There are ".tables" and ".schema [table_name]" commands which give kind of a separated version to the result you get from "select * from sqlite_master;"
There is also "pragma table_info([table_name]);" command to get a better result for parsing instead of a construction query:
sqlite> .tables
students
sqlite> .schema students
create table students(id INTEGER, name TEXT);
sqlite> pragma table_info(students);
0|id|INTEGER|0||0
1|name|TEXT|0||0
Hope, it helps to some extent...
Another useful trick is to first get all the table names from sqlite_master.
Then for each one, fire off a query "select * from t where 1 = 0". If you analyze the structure of the resulting query - depends on what language/api you're calling it from - you get a rich structure describing the columns.
In python
c = ...db.cursor()
c.execute("select * from t where 1=0");
c.fetchall();
print c.description;
Juraj
PS. I'm in the habit of using 'where 1=0' because the record limiting syntax seems to vary from db to db. Furthermore, a good database will optimize out this always-false clause.
The same effect, in SQLite, is achieved with 'limit 0'.
FYI, if you're using .Net you can use the DbConnection.GetSchema method to retrieve information that usually is in INFORMATION_SCHEMA. If you have an abstraction layer you can have the same code for all types of databases (NOTE that MySQL seems to swich the 1st 2 arguments of the restrictions array).
Try this sqlite table schema parser, I implemented the sqlite table parser for parsing the table definitions in PHP.
It returns the full definitions (unique, primary key, type, precision, not null, references, table constraints... etc)
https://github.com/maghead/sqlite-parser
The syntax follows sqlite create table statement syntax: http://www.sqlite.org/lang_createtable.html
This is an old question but because of the number of times it has been viewed we are adding to the question for the simple reason most of the answers tell you how to find the TABLE names in the SQLite Database
WHAT DO YOU DO WHEN THE TABLE NAME IS NOT IN THE DATABASE ?
This is happening to our app because we are creating TABLES programmatically
So the code below will deal with the issue when the TABLE is NOT in or created by the Database Enjoy
public void toPageTwo(View view){
if(etQuizTable.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Enter Table Name\n\n"
+" OR"+"\n\nMake Table First", Toast.LENGTH_LONG
).show();
etQuizTable.requestFocus();
return;
}
NEW_TABLE = etQuizTable.getText().toString().trim();
db = dbHelper.getWritableDatabase();
ArrayList<String> arrTblNames = new ArrayList<>();
Cursor c = db.rawQuery("SELECT name FROM sqlite_master WHERE
type='table'", null);
if (c.moveToFirst()) {
while ( !c.isAfterLast() ) {
arrTblNames.add( c.getString( c.getColumnIndex("name")) );
c.moveToNext();
}
}
c.close();
db.close();
boolean matchFound = false;
for(int i=0;i<arrTblNames.size();i++) {
if(arrTblNames.get(i).equals(NEW_TABLE)) {
Intent intent = new Intent(ManageTables.this, TableCreate.class
);
startActivity( intent );
matchFound = true;
}
}
if (!matchFound) {
Toast.makeText(getApplicationContext(), "No Such Table\n\n"
+" OR"+"\n\nMake Table First", Toast.LENGTH_LONG
).show();
etQuizTable.requestFocus();
}
}