Access Sql In VbaBuilding SQL in VBABaldy. Web. A Tutorial on Building SQL in VBAHow do I construct an SQL statement in VBA? Constructing an SQL statement in VBA can be tricky, because there are often. Access needed to construct the string. For example, proper SQL. VBA syntax, and proper referencing of controls are three common. We will cover the basics of constructing SQL statements in this FAQ, and. String concatenation. This is perhaps the most common problem area. You must include proper spacing. Spacing- -Consider: Public Function SQLTest()Dim str. SQL As String str. SQL = "SELECT * FROM tbl. Main" & _"ORDER BY [Table. ID]" Current. Db. Open. Recordset str. SQLEnd Function. When attempting to execute this procedure, we will get a run- time error. I want VBA to update the Closed field in every record to the current date. VBA to Update Field in Table. Office / Access / Windows other. This MSAccess tutorial explains how to update a date field using VBA code in Access 2003 (with step-by-step instructions). In Microsoft Access 2003/XP/2000/97, I have. MySQL Functions SQL Server Functions MS Access Functions Oracle. The SQL UPDATE Statement. The following SQL statement will update the contactname to "Juan. Access and SQL Part 2: Putting VBA. those essential rules you really need to know when working with SQL in your Access. UPDATE, FROM. To help. identify the problem, modify the code slightly to print out the SQL string to. This is the single most helpful debugging technique for. SQL statements in VBA: Public Function SQLTest()Dim str. SQL As String. str. SQL = "SELECT * FROM tbl. Main" & _"ORDER BY [Table. ID]" Debug. Print str. SQL. Current. Db. Open. Recordset str. SQLEnd Function. Now, take a look at the output (in the immediate window): SELECT * FROM tbl. Main. ORDER BY [Table. ID]Easy to see that you are missing a space between the table name and the ORDER BY. Simple enough to fix: str. SQL = "SELECT * FROM tbl. Main " & _"ORDER BY [Table. ID]"Note the insertion of a space immediately after tbl. Main. This is a common. SQL statement over multiple lines. Some. like to put a space at the end of the line, some like to put a space at the. This doesn't matter, just be consistent.- -Delimiting- -Certain types of data need certain types of delimiters to be handled properly. Numbers, strings, and dates are each handled differently. We will start with. Consider: Public Function SQLTest()Dim str. SQL As String. Dim str. My. String As String. My. String = "jason". SQL = "SELECT * FROM tbl. Main " & _"WHERE [Text. Field] = str. My. String". Debug. Print str. SQL. Current. Db. Open. Recordset str. SQLEnd Function. When attempting to open this recordset we will get a runtime error. To see why. let's look at the resulting SQL statement: SELECT * FROM tbl. Main WHERE [Text. Field] = str. My. String. Of course, this is not what we want. Where is the string "jason" in the. It is not there because we included the variable name str. My. String inside. To get this value, we need to put the variable outside of the SQL string, so. VBA can evaluate the string and then include that evaluated value into the. SQL string. Let's try: str. SQL = "SELECT * FROM tbl. Main " & _"WHERE [Text. Field] = " & str. My. String. When attempting to open this recordset, we get the same error! Why? Well, look. at the resulting SQL statement: SELECT * FROM tbl. Main WHERE [Text. Field] = jason. The problem here is just a bit more subtle. In the above statement jason. We need to surround it with a delimiter that. SQL knows means "a string". Like quotation marks (single or double). This is. where it starts getting confusing: str. SQL = "SELECT * FROM tbl. Main " & _"WHERE [Text. Field] = " & Chr$(3. My. String & Chr$(3. This is fine (for now). Look at the SQL statement: SELECT * FROM tbl. Main WHERE [Text. Field] = 'jason'Chr$(3. Here's the thing: What if the string contains a delimiter? That is, what if the. O'Toole"? str. My. String = "O'Toole"str. SQL = "SELECT * FROM tbl. Main " & _"WHERE [Text. Field] = " & Chr$(3. My. String & Chr$(3. Another error! Look at the resulting SQL statement: SELECT * FROM tbl. Main WHERE [Text. Field] = 'O'Toole'This is a problem of surprising complexity if you have to deal with strings that. You could delimit the string with double quotation. SQL = "SELECT * FROM tbl. Main " & _"WHERE [Text. Field] = " & Chr$(3. My. String & Chr$(3. SELECT * FROM tbl. Main WHERE [Text. Field] = "O'Toole"Chr$(3. This is ok. But what if the string itself contains a double quotation mark? My. String = Chr$(3. What now?" & Chr$(3. SELECT * FROM tbl. Main WHERE [Text. Field] = ""What now?""An error! What to do? Well, you could double up the delimiting quotation marks: str. SQL = "SELECT * FROM tbl. Main " & _"WHERE [Text. Field] = " & Chr$(3. Chr$(3. 4) & _ str. My. String & Chr$(3. Chr$(3. 4)SELECT * FROM tbl. Main WHERE [Text. Field] = """What now?"""This works, but isn't easy to read, and even worse fails if the string does not. The solution some like is to use to always use. Then, use a function to. The doubled- up delimiter is now treated as a. There is also more reading on this issue at the Knowledge Base: HOWTO. Query for Literal Special Characters in a Where Clause. You'll be glad to know that if you made it through all that, the hardest part is. Dates are up next, and we're going to look at the right way to. SQL in VBA as incidental. Public Function SQLTest()Dim str. SQL As String. Dim dtm. My. Date As Date. Dim rs As DAO. Recordset. My. Date = "1/1/2. SQL = "SELECT * FROM tbl. Main " & _"WHERE [Date. Field] = #" & dtm. My. Date & "#". Debug. Print str. SQL. Set rs = Current. Db. Open. Recordset(str. SQL). If Not (rs. EOF) Then. Debug. Print rs![Date. Field]Else. Debug. Print "Nothing found"End If. Set rs = Nothing. End Function. The output: SELECT * FROM tbl. Main WHERE [Date. Field] = #1/1/2. 00. Easy enough. We use octothorpes to delimit dates. You can try the above without. It's good to do this. The incidental points: We're opening the recordset and storing it in the. We are using rs. EOF to verify we got back something. This would be True if there were no matches, and if there were no matches, the recordset. Date. Field]. Non- USA Date Formats. Another tricky things to remember about dates is that Jet expects all dates to. It does not take any international date format. Control Panel into account. This means if you are storing your. SQL. Finally, we saved the easiest for last - - numbers. Now numbers are real easy. Public Function SQLTest()Dim str. SQL As String. Dim lng. My. Number As Long. Dim rs As DAO. Recordset. My. Number = 3. 0. SQL = "SELECT * FROM tbl. Main WHERE [Number. Field] = " & lng. My. Number. Debug. Print str. SQL. Set rs = Current. Db. Open. Recordset(str. SQL). If Not (rs. EOF) Then. Debug. Print rs![Textfield]Else. Debug. Print "Nothing found"End If. Set rs = Nothing. End Function. SELECT * FROM tbl. Main WHERE [Number. Field] = 3. 0tom. Really straight forward. The incidental point: note I am printing a different. I used in my criteria. That's because I'm selecting all fields using. SELECT clause. That's the basics of delimiting data for SQL statements. Next up, we will cover. SQL. statements to build a sample search form in the sample database below. Building SQL, part 2. Search form sample db.
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