I'm using ASP.NET MVC 4.5.2, entityframework 6.1.3 and Oracle 19c (19.3.0) database. I encounter a strange behavior with an EntityFramework request.
With the following request:
```
List<College> testQuery1 = unitOfWork.GetRepository<College>()
.AsQueryable()
.Where(college => college.Nom.Contains("A"))
.ToList();
```
I have the following result => **testQuery1.Count = 172**. But with this request:
```
string queryParameter = "A";
List<College> testQuery2 = unitOfWork.GetRepository<College>()
.AsQueryable()
.Where(college => college.Nom.Contains(queryParameter))
.ToList();
```
the result is **testQuery2.Count = 0**. This problem happens only with my Oracle 19.3.0.0 database, with Oracle 19.10.0.0 or 12.1.2.0 everything works fine, there is no discrepency. Here are the queries genetated by entityframework. For testQuery1:
```
SELECT
"Extent1"."ID" AS "ID",
"Extent1"."ID_LIEU_RDV" AS "ID_LIEU_RDV",
"Extent1"."ID_ADRESSE" AS "ID_ADRESSE",
"Extent1"."DSIT_NOSITE" AS "DSIT_NOSITE",
"Extent1"."CODE_COLLEGE" AS "CODE_COLLEGE",
"Extent1"."NOM" AS "NOM",
"Extent1"."CREATED_BY" AS "CREATED_BY",
"Extent1"."CREATED_DATE" AS "CREATED_DATE",
"Extent1"."MODIFIED_BY" AS "MODIFIED_BY",
"Extent1"."MODIFIED_DATE" AS "MODIFIED_DATE"
FROM "DSS"."DSS_COLLEGE" "Extent1"
WHERE ("Extent1"."NOM" LIKE '%A%')
```
and for testQuery2:
```
SELECT
"Extent1"."ID" AS "ID",
"Extent1"."ID_LIEU_RDV" AS "ID_LIEU_RDV",
"Extent1"."ID_ADRESSE" AS "ID_ADRESSE",
"Extent1"."DSIT_NOSITE" AS "DSIT_NOSITE",
"Extent1"."CODE_COLLEGE" AS "CODE_COLLEGE",
"Extent1"."NOM" AS "NOM",
"Extent1"."CREATED_BY" AS "CREATED_BY",
"Extent1"."CREATED_DATE" AS "CREATED_DATE",
"Extent1"."MODIFIED_BY" AS "MODIFIED_BY",
"Extent1"."MODIFIED_DATE" AS "MODIFIED_DATE"
FROM "DSS"."DSS_COLLEGE" "Extent1"
WHERE ("Extent1"."NOM" LIKE :p__linq__0 ESCAPE '\')
```
where p_linq_0 is equal to "%A%". If I execute these queries directly on the database, the result is the same, 172 results both times.
It happens if I replace Contains by StartsWith and EndsWith too. Do you have any idea where this strange behavior may come from ?
Thanks in advance for any insights.