Details
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Task
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Status: Closed
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Major
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Resolution: Won't Fix
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None
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None
Description
Users don't get how to use table and schema name in Ignite:
https://stackoverflow.com/questions/48723946/apache-ignite-querying-a-cache-through-an-sql-driver
The confusion comes from the interpretation of term "case-insensitive". All SQL databases work this way:
1) If I create some object and define its name without quotes, a database will convert it to upper case (sometimes lower case). Then if I query this object without quotes, a query is also transformed to upper case. This is what I call "case-insensitivity" - it doesn't matter how you refer to this object, it works still.
CREATE TABLE myTable -> CREATE TABLE MYTABLE
SELECT FROM myTable -> SELECT FROM MYTABLE -> OK
SELECT FROM MyTable -> SELECT FROM MYTABLE -> OK
SELECT FROM "myTable" -> SELECT FROM myTable -> FAIL!
2) If I create an object with quotes, then the database doesn't convert it to upper case, and the original name in quotes is the only way to access the object:
CREATE TABLE "myTable" -> CREATE TABLE myTable
SELECT FROM myTable -> SELECT FROM MYTABLE -> FAIL!
SELECT FROM MyTable -> SELECT FROM MYTABLE -> *FAIL!*SELECT FROM "myTable" -> SELECT FROM myTable -> OK
Now back to Ignite case. Our schemas are case-sensitive. so the only way to access it is through quotes:
CREATE SCHEMA "cacheName"; // This is what Ignite does internally
SELECT * FROM "cacheName".myTable -> OK
SELECT * FROM cacheName.myTable -> FAIL!
Our users know this, and all their queries are written with schema names in quotation marks. Now consider what would happen should we change schema names to case-insensitive mode:
CREATE SCHEMA cacheName;
SELECT * FROM "cacheName".myTable -> FAIL, all old quries start to fail!
SELECT * FROM cacheName.myTable -> OK, now it works